Arizona Radio Observatory

1.1_so_you_wanna_be_a_telescope_operator

2007-11-13T13:12:48-07:00

So You Wanna Be a Telescope Operator? Congratulations you are about to embark on a fascinating and exciting journey that is submillimeter wavelength radio astronomy! This manual is designed with novice to advanced radio telescope operator (T.O.) in mind. This is because most of our telescope operator positions have high turn around and usually have no real radio background whatsoever. But that’s ok, we hired you didn’t we?

1.1_the_observatory

2007-06-25T07:55:21-07:00

1.1 The Observatory The ARO 12 Meter Telescope is a general purpose radio astronomical observatory that supports spectral line and continuum observations in the atmospheric windows at 3mm (68 to 115 GHz) and 2mm (133 to 170 GHz). The facility is located on Kitt Peak, Arizona, approximately 60 miles southwest of Tucson. The Observatory was constructed in 1967 by the National Radio Astronomy Observatory, with an original surface diameter of 36 feet (11 meters). In 1984, the surface and bac…

1.1_welcome

2006-10-02T07:12:17-07:00

1.1 Welcome Welcome to the ARO. As a new operator, there is going to be a fairly steep learning curve when you start, but once you get down the basics, it’s pretty easy to keep things running smoothly. And when things are not running smoothly, all you need to do is call the appropriate contact downtown. A list of contacts along with some troubleshooting tips are available in 12 Meter Operators Troubleshooting Guide.

1.1_when_to_otf_map

2006-07-25T11:06:31-07:00

1.1 When to OTF Map In principle, the OTF technique should be a superior way to make almost any map. It is particularly efficient for large fields and relatively strong emission. In these cases, one gains considerable observing time from the low telescope overhead. We strongly recommend OTF mapping in these cases. OTF can, and has, been used to advantage for small fields and weaker lines. For small fields, however, the telescope must turn around at the end of a row more often. Weak lines…

1.2.1_proposal_preparation

2007-06-18T08:43:19-07:00

1.2.1 Proposal Preparation Your proposal should consist of the following: * a completed 12m Observing Application Cover Sheet: * [PDF version], OR * [Microsoft Word version] * a body consisting of: * a concise scientific justification for the project, not to exceed 1000 words, * an estimate of the observing time required, AND * frequencies and source coordinates to be observed

1.2.1_shift_work

2006-08-14T09:58:28-07:00

1.2.1 Shift Work The standard operating shift during the observing season (~Sept 15 to ~June 15) runs 7 days on and 7 days off. During the observing season, you'll work 12 hours a day on your ON week (5 a.m. to 5 p.m. if you're on day shift and 5 p.m. to 5 a.m. if you're on night shift). And you will alternate day shifts and night shifts every other on week. Figure 1.1 displays this schedule.

1.2.2_proposal_submission_and_refereeing

2007-06-18T08:45:24-07:00

1.2.2 Proposal Submission and Refereeing Twelve meter telescope scheduling operates on a trimester system, with proposal submission deadlines and their corresponding observing periods listed in Table 1.2. The intention of the 12m proposal system is to insure that the projects granted telescope time are of current interest and that all proposals receive a prompt scheduling decision. Proposals should be sent to Dr. Lucy Ziurys at lziurys AT as DOT arizona DOT edu.

1.2.2_start_up_and_shut_down

2006-10-02T07:14:04-07:00

1.2.2 Start Up and Shut Down Though rare, there are times when you'll have to start operations from scratch or shut operations down for an extended period of time. For complete step-by-step instructions for powering everything (computers, backends, chassis, dome) up or down, see the 12 Meter Operators Troubleshooting Guide.

1.2.3.1_corona.as.arizona.edu

2006-08-14T10:30:36-07:00

1.2.3.1 corona.as.arizona.edu Corona is the main operating computer. Suppose corona has just been rebooted. Here is what you need to do to get things started. Login as oper12m. Type > startx to get the main display. Right-click on the desktop and open LogBook, Figure 1.2, and XControl, Figure 1.3.

1.2.3.2_modelo.as.arizona.edu

2006-08-14T10:35:26-07:00

1.2.3.2 modelo.as.arizona.edu Modelo is the computer into which observers must log for remote observation or to upload catalogs or reduce data. The username for observers on modelo is obs. Each observer has a directory within the obs directory corresponding to his initials, xyz:

1.2.3.3_ballena.as.arizona.edu

2006-08-15T08:38:05-07:00

1.2.3.3 ballena.as.arizona.edu Ballena sits directly behind the operator on the rack containing the spectrum analyzer along with other chassis. It is the computer used for tuning. Up12 Meter Operators ManualPrev1.2.3.2 modelo.as.arizona.eduNext1.2.4 System Status Logging

1.2.3_computers

2006-08-15T08:36:57-07:00

1.2.3 Computers Table 1.1 is a comprehensive list of computers used at the 12m. It is only with the first three that you are likely to interact on a regular basis. Table 1.1 Computers used at the 12m Machine Operation Linux machines corona Control modelo Observers ballena Tuning tecate Data Display optical Optical telescope…

1.2.3_proposal_and_observing_propriety

2007-06-18T08:47:13-07:00

1.2.3 Proposal and Observing Propriety Observers are expected to confine their observations to those described in their refereed proposal. It is absolutely essential that observers consult with the Director and obtain her approval before altering scheduled observing programs. Approval for changes may be granted as long as they do not lead to an infringement on work proposed by others and are in keeping with the spirit of the original, refereed proposal. These rules are fundamental to the in…

1.2.4_system_status_logging

2007-06-20T11:22:50-07:00

1.2.4 System Status Logging Though not available at the time of this writing (14 August 2006), there will be a program in use starting this observing season. EDIT: The program was not installed this year, as of 20 June 2007. I do not know whether it ever will be, but if it is...

1.2_general

2006-10-02T07:12:50-07:00

1.2 General * 1.2.1 Shift Work * 1.2.2 Start Up and Shut Down * 1.2.3 Computers * 1.2.3.1 corona.as.arizona.edu * 1.2.3.2 modelo.as.arizona.edu * 1.2.3.3 ballena.as.arizona.edu * 1.2.4 System Status Logging Up12 Meter Operators ManualPrev1.1 WelcomeNext1.2.1 Shift Work

1.2_how_otf_observing_works

2006-07-25T11:05:00-07:00

1.2 How OTF Observing Works Before starting an OTF map, you configure the telescope control system for the width of the field, the scanning rate, the row spacing, and a few other things. For spectral line OTF, the map is taken in a total power observing mode in the sense that you take a calibration spectrum (a vane CAL) and a total power OFF, followed by one or more total power scanning rows, typically made up of hundreds of individual spectra (the ONs). For continuum OTF, the map is acquire…

1.2_observing_proposals

2006-07-18T08:47:46-07:00

1.2 Observing Proposals * 1.2.1 Proposal Preparation * 1.2.2 Proposal Submission and Refereeing * 1.2.3 Proposal and Observing Propriety Up12 Meter Observers ManualPrev1.1 The ObservatoryNext1.2.1 Proposal Preparation

1.2_telescope_operator_duties

2007-11-13T13:15:22-07:00

Sorry the SMT is not Disneyland! Please do NOT do any of these things: 1. The wildlife on the mountain are not for entertainment and not for eating. Leave it be, especially if it resembles a squirrel. The Mount Graham Red Squirrel is an endangered species and we live and work in its territory. ALL personnel who come across a Red Squirrel are to leave it be. If you perceive it is endangered or find one dead contact the Biologist camp on the radio and a Star Unit (that’s the UAPD) immediately! AL…

1.3.1_staff_responsibilities

2007-06-18T08:48:05-07:00

1.3.1 Staff Responsibilities The ARO staff will: * Ensure that the equipment needed for your observations is available and installed at the telescope, * Tune the receiver to the desired frequency, * Provide sound telescope pointing, * Provide fundamental telescope calibration parameters (efficiencies, beamwidths, gain curves) at standard observing frequencies, and * Provide advice on observing strategies, if requested.

1.3.2_observer_s_responsibilities

2006-09-18T08:02:38-07:00

1.3.2 Observer's Responsibilities As the visiting (or remote) observer, you are responsible for supervising all aspects of the observing program. It is your responsibility to: * Provide to the ARO staff, well in advance of the time scheduled, a full description of the equipment needed for the observations as well as a complete list of frequencies to be observed; usually this information is included on the proposal cover sheet, and * Obtain all calibration and other receiver/telescope pa…

1.3.3_maintenance_and_repairs

2007-06-18T08:54:18-07:00

1.3.3 Maintenance and Repairs One period (approximately every 14 days) is assigned to preventative maintenance and routine system tests. If during a scheduled observing period there occurs a serious instrument failure resulting in the loss of data, observations will be stopped and the ARO technical staff will attempt to repair the equipment. In less serious cases in which data-taking may continue but in which the quality of the data is not optimal, it is your responsibility to decide whether…

1.3.4_sharing_telescope_facilities_with_other_observing_teams

2006-09-13T08:47:06-07:00

1.3.4 Sharing Telescope Facilities with Other Observing Teams Since living quarters and workspaces at the telescope are limited, please try to restrict your onsite time to the period scheduled for your run, allowing a day on either side for rest. If you wish to use our facilities before the run to prepare or after the run to continue the reduction of your data sets, you are welcome to do so at the ARO Tucson office. The University campus and surrounding area are also teeming with free access…

1.3.5_observations_under_poor_weather_conditions

2007-06-25T07:57:30-07:00

1.3.5 Observations Under Poor Weather Conditions There are a variety of weather conditions that can endanger the safety of the telescope. For most of the conditions listed below, the observer must defer to the telescope operator who will determine whether it is safe to observe.

1.3.6_sun_on_the_dish

2007-06-25T09:16:53-07:00

1.3.6 Sun on the Dish The pointing and focus of the dish can be seriously affected if the sun is allowed to shine on the surface of the dish or the feed support legs. If accurate pointing is desired, care must be taken to keep the sun off the dish. To avoid excessive heating of the feed legs, the prime focus regions, and the cables to the prime focus, the dish must not be pointed to within 15 degrees of the sun. The projected distance between the sun and a position on the sky defined as (AZ…

1.3.7_observations_using_emergency_power_generators

2006-09-13T09:39:42-07:00

1.3.7 Observations Using Emergency Power Generators The telescope and dome have three sources of electric power - the commercial source and two power generators. Observations can continue as long as at least two of the sources are operational. If only one source of power is available, the dome door must be closed.

1.3_an_important_note_about_spatial_sampling

2006-08-29T08:33:28-07:00

1.3 An Important Note About Spatial Sampling The following discussion is thanks to Darrel Emerson When setting up your map observations, it is important to keep in mind the following facts about sampling and aliasing in radio astronomical mapping data. If you want to represent the full resolution of the telescope, you have to sample the data often enough to represent all the spatial frequencies detected by the dish. You can think of the extreme edges of the dish of diameter D as part of an …

1.3_observatory_policy

2006-09-13T09:41:32-07:00

1.3 Observatory Policy * 1.3.1 Staff Responsibilities * 1.3.2 Observer's Responsibilities * 1.3.3 Maintenance and Repairs * 1.3.4 Sharing Telescope Facilities with Other Observing Teams * 1.3.5 Observations Under Poor Weather Conditions * 1.3.6 Sun on the Dish * 1.3.7 Observations Using Emergency Power Generators

1.3_observing_run_overview

2007-06-20T11:23:22-07:00

1.3 Observing Run Overview Anytime a new observer starts a program, these are the steps you must follow to get things going: * Change the observer initials * Ask the observer for the observing parameters: * Frequency of observation, which must be between 68 and 90 GHz (3mmlo), between 90 and 115 GHz (3mmhi), or between 133 and 170 GHz (2mm) * Backend setup (filterbank configuration and MAC configuration) * Observation type and length of time per scan * Source catalog and sour…

1.3_operator_shift_schedule

2007-11-13T13:14:48-07:00

There are four full time telescope operators. Two of them work one week and the other two will have one week off. Either you will be the Wednesday to Wednesday operator during the week or the Friday to Friday operator for the week. All the T.O.'s decide at the beginning of the observing season which day of the week they will always start their shift on for the entire season. Meaning, you work a week on and then have the next week off, always starting and ending your shift on the same day of the …

1.4_observing_schedule

2007-11-13T13:13:32-07:00

The Observer Schedule is the same thing as the Telescope Schedule listed on the ARO website (see link below). It is notorious for last minute changes. Therefore, as an operator you should always reload the web page link at the beginning of each shift, to make sure you are looking at the most up to date schedule. Any scheduling issues call Tom Folkers. Issues arise often since astronomers are also notorious for not double checking their time on our website.

1.4_other_sources_of_information

2006-08-29T08:42:45-07:00

1.4 Other Sources of Information D. T. Emerson, "Increasing the Yield of our Telescopes", in Proceeding to IAU 170, CO: 25 Years of Millimeter-Wavelength Spectroscopy E. Greisen, "Single-Dish Data in Aips", Chapter 10, AIPS Cookbook J. G. Mangum, D. T. Emerson, & E. Greisen, "The On-The-Fly Observing Technique", in Proceedings to Imaging at Radio through Submillimeter Wavelengths.

1.4_safety_rules

2007-06-18T09:08:04-07:00

1.4 Safety Rules The following safety rules apply to the 12 Meter Telescope site. We expect all observers and visitors to the site to read and abide by these rules: * The Telescope Operator on duty is the only person allowed to operate the telescope. * Observers are not to be on the telescope platform unless the duty operator has specifically authorized them to be there. * Safety rails have been installed at the entrance to the observing rooms. They are there to prevent you from w…

1.5_the_smt_building

2007-11-13T13:14:45-07:00

The SMT building has 5 levels and no elevator of any kind. The ground level is the entry level, outside is the gas grill, inside contains 5 dorm rooms, the utility room and the machine shop. The second floor contains the common areas such as the kitchen the lounge, and a bathroom. The electronic shop is also located on this floor, but it is not a shared common space with everyone on-site. Also, on the second floor is a circular metal carousel around the outer circumference of the second floor wa…

1.6_mgio_uapd_on_site_policies_and_help

2007-11-13T13:15:27-07:00

Telescope Operators read the following section carefully BEFORE your first visit to Mt. Graham. Please also have on site visitors read as well. Mount Graham International Observatory, MGIO, and the University of Arizona Police Department, UAPD, are on-site to provide support to each of the three observatories. MGIO is a division of Steward Observatory and the UAPD officers are state licensed troopers, who are employed by the University of Arizona and have jurisdiction all over Arizona.

1.7_observer_remote_login_issues

2007-11-13T13:15:03-07:00

The majority of the SMT users observe with a remote login protocol. When a group's proposal is awarded time, Tom Folkers or Lucy Ziurys, will email the the time allotment and a link to the instructions on how to do a remote login session. New users to the SMT often ask operators about this feature. Therefore, it is important to visit the link and become familiarize with it. Remote Observing Instructions

1.7_smt_observers

2007-11-13T13:13:36-07:00

Our “customers” are astronomers who are awarded time on the SMT after submitting an observing proposal. ARO Proposal Submission Link Due to funding constraints it is often we have a “paying customer” and this is usually international groups, that pay Arizona Radio Observatory (ARO) for time on the telescope. These observers always have the highest priority and are usually rescheduled later if they lose time to weather. It is very important that the Telescope Operator (T.O.) keeps a record, in …

1.8_other_mt._graham_information

2007-11-13T13:14:42-07:00

There are 3 telescopes on Mt. Graham. All have some participation from the University of Arizona Steward Observatory Department. The SMT is the only telescope fully owned by Steward Observatory, S.O. Website, on Mt. Graham. The Large Binocular Telescope, LBT, blocks our eastern rising ecliptic objects. Its construction phase is complete and is now in the instrument development and testing phase. It is administered by the Steward Observatory, but is owned by many institutions working in partnersh…

12_meter_atmospheric_model

2006-09-06T07:58:49-07:00

Until the end of the 2003-2004 season, spectral line data taken with the 12 Meter telescope were converted to temperature units using a nominal fixed value for the calibration scale temperature. This value was relatively accurate for typical atmospheric conditions and frequencies not very close the edges of the different atmospheric windows accessible by the current facility receivers.

12_meter_computer_replacement_project

2007-06-20T10:41:34-07:00

Update as of August 2006: All computers have been replaced, and the control system has been recompiled under Linux. All cross-compiling for the backends has been addressed and is functioning normally. Even the Apex computer, which was already running Linux, has been upgraded to a new operating system version. All drivers have been updated to the 2.4.22 kernel version.

12_meter_documentation

2006-09-14T06:46:40-07:00

Observers' Information * 12 Meter Observers Manual * Remote Observing at the ARO * PDFs * 12 Meter Atmospheric Model * 12 Meter Computer Replacement Project * 12 Meter Receivers * 12 Meter Receiver Tsys Info * 12 Meter Standard Spectra * 12 Meter Telescope * KPNO Web Site * Road Maps to Kitt Peak * On The Fly Observing * Current Telescope Status * 12 Meter Proposal Page * Paper-Based Documentation

12_meter_documents

2006-09-06T10:31:33-07:00

* Frontends * 23mmsis * [Gunn Voltage Relay Circuit] * 1mmsis * [Gunn Voltage Relay Circuit] ---------- * Backends * Filterbanks * 2 MHz Filter IF Processor * [Original Schematic] * [Modified Schematic] * Filter Bank Switcher * [Board Layout] * [Schematic Drawing]

12_meter_observers_manual

2007-06-20T09:06:04-07:00

* Preface Chapter 1: Introduction * 1.1 The Observatory * 1.2 Observing Proposals * 1.2.1 Proposal Preparation * 1.2.2 Proposal Submission and Refereeing * 1.2.3 Proposal and Observing Propriety * 1.3 Observatory Policy * 1.3.1 Staff Responsibilities * 1.3.2 Observer's Responsibilities * 1.3.3 Maintenance and Repairs * 1.3.4 Sharing Telescope Facilities with Other Observing Teams * 1.3.5 Observations Under Poor Weather Conditions * 1.3.6 Sun on the Dish * …

12_meter_operators_manual

2006-09-06T08:11:57-07:00

* 1 Introduction * 1.1 Welcome * 1.2 General * 1.2.1 Shift Work * 1.2.2 Start Up and Shut Down * 1.2.3 Computers * 1.2.3.1 corona.as.arizona.edu * 1.2.3.2 modelo.as.arizona.edu * 1.2.3.3 ballena.as.arizona.edu * 1.2.4 System Status Logging

12_meter_operators_troubleshooting_guide

2006-09-06T08:13:33-07:00

Here's your troubleshooting guide for operating the 12m. What follows is a comprehensive list of everything that went wrong during the 2005-2006 observing season including how it might be handled, links to the corresponding operator daily log(s), and the appropriate contacts if the troubleshooting still doesn't work.

12_meter_proposal_page

2007-06-20T11:17:32-07:00

12 Meter Proposal Page The Arizona Radio Observatory (ARO) is currently accepting observing proposals for the 12 Meter for the 2007 - 2008 observing season. The telescope is being operated through Steward Observatory with funds provided by the University of Arizona and the Research Corporation.

12_meter_receiver_tsys_info

2006-09-20T07:47:04-07:00

Please consult Table 3.2 in §3.3 of the 12 Meter Observers Manual. Up12 Meter DocumentationPrev12 Meter ReceiversNext12 Meter Standard Spectra

12_meter_receivers

2006-08-31T08:06:55-07:00

Please consult §3.3 of the 12 Meter Observers Manual. Up12 Meter DocumentationPrev12 Meter Computer Replacement ProjectNext12 Meter Receiver Tsys Info

12_meter_shutdown_2006

2006-09-28T14:31:22-07:00

Documentation Job Who? Priority Done Chemical inventory for MSDS Compliance Karen 1 X Wikipedia update of User Manual and general ARO documentation Erin 1 X

12_meter_shutdown_2007

2007-06-18T10:04:05-07:00

Documentation Job Who? Priority Done Update ARO Wiki Erin 3

12_meter_standard_spectra

2006-09-20T08:38:01-07:00

Please consult Table 4.2 in §4.6 of the 12 Meter Observers Manual. Up12 Meter DocumentationPrev12 Meter Receiver Tsys InfoNext12 Meter Telescope

12_meter_telescope

2006-08-31T08:24:26-07:00

12 Meter Telescope Please consult §1.1 and §3.2 of the 12 Meter Observers Manual for information on the telescope. Up12 Meter DocumentationPrev12 Meter Standard SpectraNextKPNO Web Site

1_introduction

2006-09-18T07:48:34-07:00

Chapter 1 Introduction * 1.1 The Observatory * 1.2 Observing Proposals * 1.2.1 Proposal Preparation * 1.2.2 Proposal Submission and Refereeing * 1.2.3 Proposal and Observing Propriety * 1.3 Observatory Policy * 1.3.1 Staff Responsibilities * 1.3.2 Observer's Responsibilities * 1.3.3 Maintenance and Repairs * 1.3.4 Sharing Telescope Facilities with Other Observing Teams * 1.3.5 Observations Under Poor Weather Conditions * 1.3.6 Sun on the Dish * 1.3.7 Ob…

1_operators_introduction

2006-08-14T09:43:13-07:00

This is the Operators’ Manual for operation of the 12-Meter Telescope at the Arizona Radio Observatory (ARO). Enjoy! Note that this is meant more as a step-by-step instruction book than as a theoretical discussion of the capabilities of the 12m. If you are interested in a theoretical discussion, please see 12 Meter Observers Manual.

1_otf_introduction

2006-08-29T08:32:22-07:00

On-the-fly (OTF) mapping is an observing technique in which the telescope is driven smoothly and rapidly across a field while data and the antenna position information are recorded continuously. This technique is in contrast to the traditional mapping of discrete positions on the sky, which is usually called grid mapping.

2.1.1_liebert_ups_procedure

2007-11-13T13:13:20-07:00

Electrical power to the Mt. Graham site is the responsibility of MGIO. The Liebert UPS is the main uninterruptible power supply for the entire SMT building and is our only defense against power failures which occur frequently onsite. All smaller or “spot” UPS’s are also plugged into the main Liebert UPS, they are the outlets marked with an orange triangle. The following are scenarios with power that will include actions for the telescope operator to follow.

2.1.2_power_shut_down

2007-11-13T13:13:24-07:00

Computers 1. Turn off LINUX based computers by right click on the xwindow screen and “EXIT” windows. At prompt login as “root” and type root password. 2. At root login prompt type “halt” 3. When system halts, turn power off the computer and monitor.

2.1.3_power_start_up

2007-11-13T13:15:00-07:00

Maser Record 28+V for Bob Freund in log. UPS 1. Once on generator or commercial power, check the JT and cold head compressors are back online on the 5th Floor. 2. Turn on all spot UPS’s 3. Call Tom Folkers and tell him once the computers are ready to start back up.

2.1_emergency_power_down_and_power_up_procedures

2006-08-29T18:23:47-07:00

* If applicable, start compressors and cold-heads. * Record the maser values. * Start Liebert UPS * Start all spot UPS units. * APC Units: * Inside Filter Rack. * Inside Tracker/Servo Rack. * Behind smtotux. * Inside DBE Rack. * Next to FMS rack. * Observers one next to doxx. * One for Amana.

2.1_emergency_procedures

2007-11-13T13:11:03-07:00

This section is full of links for diffierent types of emergencies. For example, bad weather usually causes issues for site power. Therefore, there are many links pertaining to power loss and shut down. Click below for Commercial Power Failure: [:wiki:powerfailurechart.pdf]

2.1_harming_the_frequency

2006-10-02T07:33:38-07:00

2.1 Harming the Frequency When the observer tells you the frequency of observation, use RAMBO to set the frequency. On the RAMBO Utilities screen, open Receiver, Figure 2.1. Figure 2.1 RAMBO Receiver Screen On the left of the Receiver screen, select the appropriate bandpass for the frequency. Next set the frequency, in one of three ways:

2.1_otf_observing_checklist

2006-08-29T08:55:52-07:00

2.1 OTF Observing Checklist The following list gives some step-by-step instructions that you can use as a guide to acquiring and processing OTF data. The section to which you should refer to for further information is indicated in each item. For Spectral Line OTF:

2.1_what_to_bring_to_the_telescope

2007-06-18T09:11:07-07:00

2.1 What to Bring to the Telescope Your observations will be more efficient and you will achieve better results if you have thoroughly prepared for your observing run before arriving at the telescope. Most of this work should be done at the time the proposal is written (see Chapter 1). For both spectral line and continuum observations, you should prepare the following before coming to the telescope:

2.2.1_row_sampling_rate

2006-09-20T10:13:12-07:00

2.2.1 Row Sampling Rate It is very important that you set up your map to be properly sampled perpendicular to the scanning direction. If you undersample, * you will miss information in the image field, * you will be unable to accurately combine your image with that from interferometers or other single-dish telescopes, and * you may introduce artifacts from the analysis algorithms.

2.2.2_scanning_rate

2006-09-20T10:29:51-07:00

2.2.2 Scanning Rate Your map must also be sampled properly in the scanning direction. Since the spectrometers must integrate for a finite interval before being dumped, the data are “square-box” binned. To avoid noise aliasing and beam-smearing problems, one needs to oversample in the scanning direction. The scan rate may be written as,

2.2.3_row_length_limitations

2006-09-20T10:33:20-07:00

2.2.3 Row Length Limitations Since the telescope acquires a data sample every 0.1 s (for spectral data) or 0.25 s (for continuum data), the combination of the telescope slew rate and the scan length in RA determines how much data you get per row. Due to software and practical restrictions, the maximum number of samples one can acquire in a given scan is 3600. This corresponds to a slew rate of 10 ”/s over a scan which is 1º in length. You should set your observing parameters to stay below t…

2.2.4_bad_channel_flagging

2006-09-20T10:36:04-07:00

2.2.4 Bad Channel Flagging It is a good idea to flag bad filterbank channels before processing the data. Therefore, before you begin your OTF map, identify any bad filterbank channels by making a normal position-switch test measurement of your source. Use the badch procedure in UniPOPS or draw command in CLASS to identify the bad channels and tell the operator that you want these channels to be flagged.

2.2.5_map_rms

2006-09-20T13:19:16-07:00

2.2.5 Map RMS When planning an OTF observing run you must calculate how much integration time you need for each sampling cell to reach the desired signal-to-noise level. First determine the integration time required using the standard Radiometer Equation,

2.2.6_total_map_time

2006-09-21T07:27:05-07:00

2.2.6 Total Map Time The total time required to acquire a map must include not only the integration time scanning across the field but also the time for calibration and OFF integrations. This can be written as [2.14] where Nrow = number of rows in the map,

2.2.7_doppler_tracking

2006-09-21T07:26:23-07:00

2.2.7 Doppler Tracking The default reference position for Doppler tracking of OTF maps is the map center position. It is possible to change these settings to Doppler track relative to any RA and Dec. UpOn The Fly ObservingPrev2.2.6 Total Map TimeNext2.3 OTF Map Setup

2.2_building_drive_operation_and_troubleshooting

2007-11-13T13:12:28-07:00

What are the building drives? They are the two large blue colored boxes overhead on the carousel that contain the electric motors, which move the rotating part of the building (in azimuth - it is referred as the “azimuth drive”). The motors drive the two types of wheels along two types of tracks, the normal track and the lateral track. The normal wheels are the larger ones and are perpendicular to the large silver track seen as you go up the stairs from the 2nd to the 3rd floor. These are the …

2.2_otf_map_parameters

2006-09-20T08:44:01-07:00

2.2 OTF Map Parameters Here are some of the OTF map parameters that you must consider in order to setup your OTF observing. UpOn The Fly ObservingPrev2.1 OTF Observing ChecklistNext2.2.1 Row Sampling Rate

2.2_startup_checklist

2007-06-18T09:49:04-07:00

2.2 Startup Checklist A general startup checklist for both spectral line and continuum observations is given below. Although the Observatory staff tries to provide a fully functional system and advice about calibration constants and procedures, the responsibility for the integrity of the data rests with the observer. This checklist will help ensure that the system is configured properly and that variable quantities such as pointing and focus are properly set. Completion of this checklist ma…

2.2_switching_the_optics

2006-08-14T11:22:16-07:00

2.2 Switching the Optics Next you must set the optics in the appropriate position for the specific bandpass. Table 2.1 indicates what goes where and the figures below the table may provide more illumination. Don't worry, someone will show you how to manipulate all the knobs and dials.

2.3_basic_data_reduction_with_unipops

2007-06-25T12:26:51-07:00

2.3 Basic Data Reduction with UniPOPS The official data reduction software at the 12m is UniPOPS. See Unipops Documentation for help with data reduction. Up12 Meter Observers ManualPrev2.2 Startup ChecklistNext2.4 Basic Data Reduction with CLASS

2.3_otf_map_setup

2006-09-21T09:22:52-07:00

2.3 OTF Map Setup When you give your map setup parameters to the operator, he will fill in a menu like the one shown in Figure 2.3. Figure 2.3 OTF Map Setup Table 2.1 describes each of these parameters and indicates how they should be set for both types of OTF map.

2.4_basic_data_reduction_with_class

2006-09-13T09:44:22-07:00

2.4 Basic Data Reduction with CLASS Another data analysis package available at the 12m is CLASS. Along with ASTRO, it is part of the GILDAS package from the Grenoble Observatory and was designed specifically for (sub)millimeter data reduction. Please see CLASS Documentation for ARO-specific CLASS reduction guidelines.

2.4_data_file_management

2006-09-21T09:47:00-07:00

2.4 Data File Management Spectral line OTF generates a great deal of data. When in OTF mode, the data rate for the filterbanks is 3.1 Mbytes/minute, while for the MAC the rate is 11.7 Mbytes/minute when observing in 2048 channel mode, and 159.1 Mbytes/minute when observing in 32768 channel mode.

2.5_data_archiving_and_export

2007-06-18T10:01:03-07:00

2.5 Data Archiving and Export You are welcome to reduce your data on our machines or sftp them to your own computer to work with them. Simply sftp from your machine to modelo and login as obs, then cd to your /home/obs/ini/ directory, from which you can get any and all the files you need.

2.5_health_care

2007-04-21T09:35:14-07:00

2_getting_started

2006-09-13T09:45:21-07:00

Chapter 2: Getting Started * 2.1 What to Bring to the Telescope * 2.2 Startup Checklist * 2.3 Basic Data Reduction with UniPOPS * 2.4 Basic Data Reduction with CLASS * 2.5 Data Archiving and Export Up12 Meter Observers ManualPrev1.4 Safety RulesNext2.1 What to Bring to the Telescope

2_observing_setup

2006-07-25T11:15:45-07:00

2 Observing Setup]] * 2.1 OTF Observing Checklist * 2.2 OTF Map Parameters * 2.2.1 Row Sampling Rate * 2.2.2 Scanning Rate * 2.2.3 Row Length Limitations * 2.2.4 Bad Channel Flagging * 2.2.5 Map RMS * 2.2.6 Total Map Time * 2.2.7 Doppler Tracking * 2.2.8 Examples

2_setting_the_frequency

2006-08-14T11:09:25-07:00

* 2.1 Harming the frequency * 2.2 Switching the optics Up12 Meter Operators ManualPrev1.3 Observing Run OverviewNext2.1 Harming the Frequency

3.1_dataserv

2006-09-21T10:11:05-07:00

3.1 Dataserv Dataserv is a general utility program for automatically displaying all types of 12 Meter data on an X Window system in real time. During conventional observing, Dataserv automatically displays the filterbank and MAC spectra.as well as continuum observations such as five-points and focus checks.

3.1_telescope_site_layout

2007-06-25T09:29:19-07:00

3.1 Telescope Site Layout The 12m is located on the southwest ridge of Kitt Peak, about two miles below the top of the mountain. A drawing of the 12m site layout is shown in Figure 3.1. See Road Maps to Kitt Peak for directions to the site. Figure 3.1 - 12m Site Layout Three rooms are available in the dome for observer use. During scheduled observing time, you will normally want to sit in the control room at the observer's console so that you can communicate with the operator. An adja…

3.2_databrowse

2006-09-21T10:19:51-07:00

3.2 Databrowse Databrowse will let you get a quick look at any previous Dataserv display. This includes OTF mapping and other spectral and continuum scans. You can start Databrowse from the “Observer Tools” pull-down menu of your obs session. Databrowse has a variety of options for displaying your data. Information and help on its use can be found within its internal help facility.

3.2_telescope_optics

2007-06-18T10:07:24-07:00

3.2 Telescope Optics The 12m employs bent Cassegrain optics for all the receivers used by visiting observers. A few test and special purpose receivers including the holography receiver are mounted at the prime focus. A diagram of the optics is given in Figure 3.2.

3.3.1_the_4_color

2007-11-13T13:15:06-07:00

The 4 Color Bolometer is still in working order and bolted onto the right flange when in use. However, the aluminium support frame was taken down during the Summer shutdown of 2004 and stored into pieces behind the DBE rack on the right flange side. It is possible for astronomers to use this instrument ONLY if they have wrote a proposal specifically requesting to use it and the ARO staff astronomer has scheduled it into the official SMT schedule, allowing time to reassemble the frame and cool d…

3.3_receivers

2007-06-25T09:52:13-07:00

3.3 Receivers NB. The 12m no longer has a 1mm receiver. 1mm observations may be conducted at the SMT. The receiver at the 12m employs heterodyne mixers (sometimes called coherent detectors) which use superconducting-insulating-superconducting (SIS) junctions. The SIS junctions are housed in a dewar which is part of a closed-cycle cryostat with temperature stages at 20 K and 4 K. The 20 K stage is cooled by a conventional compressed helium refrigerator system; the 4 K stage is cooled by a s…

3.3_the_bolometers

2007-11-13T13:12:42-07:00

Bolometers that are made to work in the submillimeter range have been single pixel arrays, that collect photons from continuous objects. The 19 Element Bolometer Array (Currently unavailable) In March 2000, the MPIfR 19-channel 870 micron bolometer array arrived. It was installed and quickly has become a favorite with both Steward and MPIfR observers. Currently, the standard observing modes include both CONOFF (a simple continuum on-off scan) and CMAP (On-the-fly mapping) modes. Data reduction…

3.4_the_1.3mm_to_2mm_jt_receiver

2007-11-13T13:14:52-07:00

The 1.3mm AL receiver is the SMT main workhorse receiver. It is the most requested receiver and has the best system temperatures. This receiver has 2 ALMA test mixers. These are an experimental design for the next generation of submillimeter mixers for the ALMAproject in Chile. With this configuration the SMT now has one receiver that can observe in single or dual polarizations, just by selecting the appropriate IF Routing! These mixers are called “tunerless”, because they are completely control…

3.4_the_local_oscillator_system

2007-06-18T10:28:42-07:00

3.4 The Local Oscillator System Mixer receivers require a local oscillator signal. For spectral line work, the LO signal must be phase- and frequency-stable to an accuracy of at least 1 part in 105. The purpose of the LO system is to phase-lock the LO source, which is otherwise a free-running oscillator. LO sources used at the 12m are solid-state gunn oscillators. The power required of the LO source by present generation millimeter-wave mixers precludes the direct use of a harmonic of a lo…

3.5_the_if_section

2007-06-18T10:34:37-07:00

3.5 The IF Section The receiver at the 12m produces an intermediate frequency of 1.5 GHz. The IF signal emerging from the receiver dewar must be further amplified and processed before detection by the backends. A two-channel IF system situated on the telescope performs this function.

3.6.1_filterbanks

2007-06-25T10:00:16-07:00

3.6.1 Filterbanks The 12m has eight filter spectrometers available for spectral line work. The multiplexer will provide two spectra with up to 512 spectral channels. It is always possible, therefore, to record the output of two filterbanks simultaneously. Except for the 30-kHz bank, all of the filterbanks have two independent 128-channel sections. You can configure these banks in one of two ways. In Series Mode, the two sections are placed end to end in frequency space, i.e., the 256 chan…

3.6.2_millimeter_autocorrelator_mac

2007-06-25T10:28:01-07:00

3.6.2 Millimeter Autocorrelator (MAC) The Millimeter Autocorrelator is a correlation spectrometer with a digital section similar in design to that used at the Green Bank Telescope (GBT). The full bandwidth for any given observation is pre-filtered through a set of anti-aliasing filters, and then each IF is sampled in three levels and autocorrelated.

3.6.3_continuum_backend

2006-07-19T09:48:41-07:00

3.6.3 Continuum Backend Continuum data at the 12m is acquired by a two-channel, four-phase digital backend (DBE). The DBE can record two switch phases and two calibration phases. The calibration phases can be generated by the synchronous emission of a noise diode, which is available at 3 mm wavelengths only (no longer in use). The DBE also generates a signal/reference pulse to move the subreflector at a default switching rate of 4.0 Hz, so that each phase of a four-phase switching cycle las…

3.6_spectrometers

2006-07-26T09:36:27-07:00

3.6 Spectrometers * 3.6.1 Filterbanks * 3.6.2 Millimeter Autocorrelator (MAC) * 3.6.3 Continuum Backend Up12 Meter Observers ManualPrev3.5 The IF SectionNext3.6.1 Filterbanks

3.7_computer_equipment

2007-06-25T12:25:59-07:00

3.7 Computer Equipment The 12 Meter Telescope computer system is composed of a network of Linux workstations. The telescope control and primary data analysis functions are controlled by a quad-processor Intel Xeon PC. The control program is a C-language-based interface package called RAMBO. The RAMBO interface handles all of the functions of data acquisition, including communication with the VxWorks device drivers that run the spectrometers, receivers, and other devices associated with a pa…

3.7_the_7_pixal_array_desert_star_-_345_ghz

2007-11-13T13:14:56-07:00

currently retired Desert Star is an array receiver, designed by Dr. Chris Walker's SORAL Group at The University of Arizona Steward Observatory department. It has a 315-380 GHz 7-element array and was made for the SMT. Desert Star Return To T.O. Manual Table of Contents

3_instrumentation

2006-07-26T06:21:04-07:00

Chapter 3: Instrumentation * 3.1 Telescope Site Layout * 3.2 Telescope Optics * 3.3 Receivers * 3.4 The Local Oscillator System * 3.5 The IF Section * 3.6 Spectrometers * 3.6.1 Filterbanks * 3.6.2 Millimeter Autocorrelator (MAC) * 3.6.3 Continuum Backend

3_locking_the_gunn

2007-06-25T07:17:51-07:00

BEFORE you lock the gunn and tune the frequency, check whether there are any saved tunings at the same or a nearby frequency. On the tune screen, click auto, select the desired frequency, click load state. You will still have to follow the directions to check that the gunns are locked, that there is enough rejection, and that the y-factor is high enough. But a saved tuning at your frequency will make for a much better starting point.

3_online_data_monitoring

2006-09-21T09:53:59-07:00

The full reduction of an OTF map can be done in about 10 minutes by an experienced user. More elaborate massaging of the data can take much longer, of course. Since it is difficult for one observer to keep up with both the data analysis and keep an eye on the progress of a current OTF map, we have developed tools that will allow you to take a quick look at your OTF data as they are being taken and to view previous maps while taking new data.

4.1.1_sidereal_objects

2007-06-25T10:54:31-07:00

4.1.1 Sidereal Objects The positions of sidereal sources should be entered into source catalogs by the observer. Sidereal source positions may be given as: * Apparent equatorial positions (already precessed), * Equinox B1950 or J2000 equatorial positions, or * Galactic coordinate positions (lII, bII).

4.1.2_ephemeris_objects

2007-06-25T10:58:47-07:00

4.1.2 Ephemeris Objects For the telescope to track ephemeris objects such as comets and asteroids, the observer must provide an ephemeris file for the object. The planets (plus Pluto), the Sun, and the Moon are automatically tracked by the 12m. We have a simple script for generating the ephemeris file. It is based on the HORIZONS System from NASA's Jet Propulsion Laboratory.

4.1_analysing_otf_data_in_unipops

2006-09-21T10:30:55-07:00

4.1 Analysing OTF Data in UniPOPS In Line, to access OTF scans, type getotf(.,); page show For example, supposing each row had 600 spectra (60 s / 0.1 s/spectrum) and you wanted to see a spectrum for the first channel of the MAC in the middle of Row 40, you would write,

4.1_tracking_capabilities

2007-06-18T10:59:20-07:00

4.1 Tracking Capabilities The 12 Meter Telescope can track both stationary (sidereal) sources or fast-moving (ephemeris) sources such as planets, comets, or satellites. It automatically calculates the current Azimuth and Elevation of an object based on its RA/Dec or Galactic or other coordinates and on the Local Sidereal Time (LST). In turn it precisely calculates the LST using the Global Positioning System.

4.1_tuning_a_frequency_on_the_3mmhi_band

2006-08-14T13:31:30-07:00

4.1 Tuning a Frequency on the 3mmhi Band If you're starting from a SAVED TUNING, check whether you have mixer current, rejection, and y-factor. You may need to make a few adjustments or start over depending on these parameters. If you're starting from scratch, simply follow these steps.

4.2.1_elevation_limits

2006-07-19T13:15:26-07:00

4.2.1 Elevation Limits Lower Limit: When the telescope reaches a lower elevation of 15.0º, it begins to depress a safety spring on the elevation stop. Tracking can continue until the elevation drive motor begins drawing excessive current; this usually occurs at an elevation near 14.5º. A final limit switch is tripped at 13.8º elevation.

4.2.2_azimuth_limits

2007-06-18T11:09:17-07:00

4.2.2 Azimuth Limits To prevent the over-wrapping of cables, the telescope has hardware and software azimuth limits. The control system will not allow the telescope to rotate through 66.8º azimuth. As they rise, sources with declinations between 27º and 38.75º will pass through 66.8º azimuth above 15º elevation. When a rising source reaches an azimuth of 66.8º, the telescope will rotate 360º to re-acquire the source. The region of the sky where azimuth transitions occur is displayed in Fig…

4.2_analysing_otf_data_in_class

2006-09-21T10:33:31-07:00

4.2 Analysing OTF Data in CLASS Please see Converting OTF Data to CLASS for a step-by-step guide to dealing with OTF data in CLASS. UpOn The Fly ObservingPrev4.1 Analysing OTF Data in UniPOPSNext4.3 Analysing OTF Data in AIPS

4.2_pointing_runs

2007-11-13T13:14:39-07:00

A Pointing Run is done in optical or spectral line/continuum. Pointing runs function as a way for the SMT to calibrate where the telescope points on objects. It is done with computer programs that make program adjustment to compensate for any offsets.

4.2_tracking_limits

2006-07-19T13:10:20-07:00

4.2 Tracking Limits Mechanical limits constrain the movement of the telescope on both the azimuth and elevation axes. Under normal source-tracking operation, the control system software prevents the telescope from moving into these limits. The telescope is also equipped with fail-safe hardware limit switches that will turn the drive motors off and apply the brakes before the telescope can be damaged.

4.2_tuning_a_frequency_on_the_3mmlo_band

2006-09-27T08:04:07-07:00

4.2 Tuning a Frequency on the 3mmlo Band These directions are identical to those in §4.1. They are repeated here verbatim for the sake of explicitness. If you're starting from a SAVED TUNING, check whether you have mixer current, rejection, and y-factor. You may need to make a few adjustments or start over depending on these parameters. If you're starting from scratch, simply follow these steps.

4.3_analysing_otf_data_in_aips

2006-09-21T10:36:16-07:00

4.3 Analysing OTF Data in AIPS AIPS is not available at the 12m. See AIPS Documentation for more information. UpOn The Fly ObservingPrev4.2 Analysing OTF Data in CLASSNext5 OFF Scan Editing Utilities

4.3_tracking_error_tolerance

2006-09-18T09:41:55-07:00

4.3 Tracking Error Tolerance The 12 Meter Telescope is vulnerable to tracking errors caused by wind gusts. The tracking software has a provision for rejecting from the integration any data sample that was taken with the telescope off-target. The basic timing cycle of the 12m control system is 100 ms. After each 100-ms interval, the system checks for error conditions such as tracking errors or a loss of frequency phase lock. If an error condition is detected, the data sample collected durin…

4.3_tuning_a_frequency_on_the_2mm_band

2006-09-27T08:03:05-07:00

4.3 Tuning a Frequency on the 2mm Band If you're starting from a SAVED TUNING, check whether you have mixer current, rejection, and y-factor. You may need to make a few adjustments or start over depending on these parameters. If you're starting from scratch, simply follow these steps.

4.4_sequence_of_position_computation_operations

2007-06-18T11:24:56-07:00

4.4 Sequence of Position Computation Operations The sequence of computer operations that is executed when seeking and then tracking a source is as follows: * Input RA/Dec (B1950, J2000, or other epoch) or Galactic (lII,bII). * If RA/Dec coordinates are inputted, first precess to current date. If Galactic coordinates are inputted, first precess to epoch B1950 then precess to current date. The precessed position of a source is computed only when the source is first accessed. * If the s…

4.5_subreflector_beam_throw

2006-09-14T07:25:30-07:00

4.5 Subreflector Beam Throw The 12 Meter Telescope is equipped with a nutating (chopping) subreflector that is used for beam-switched observations in both the spectral line and continuum modes. Other observing modes, such as position switching, are made with the subreflector locked in place.

4.6.1.1_continuum_five-point_analysis_in_unipops

2007-06-19T06:23:52-07:00

4.6.1.1 Continuum Five-Point Analysis in Unipops NB. CONDAR is currently offline. The documentation below will be valid again when CONDAR returns online. Continuum five-point measurements are processed automatically by the online dataserver. The results from these online fits are sent automatically to the operator for entry into the control system. To process a continuum five-point measurement manually, use the condar resident procedure five, which can be abbreviated as f. You can look …

4.6.1.2_spectral_line_five-point_analysis_in_unipops

2007-06-19T06:26:50-07:00

4.6.1.2 Spectral Line Five-Point Analysis The display of the map and the fit for pointing offsets is somewhat more involved than for a continuum five point. There is a standard Line procedure that processes all types of spectral line five-point measurements. To process a measurement, within Line type:

4.6.1_continuum_and_spectral_line_five-point_measurements

2007-06-19T06:23:10-07:00

4.6.1 Continuum and Spectral Line Five-Point Measurements The continuum five-point is the standard observing technique for determining the antenna pointing of the 12 Meter Telescope. Spectral line pointing is an option when continuum sources are unavailable. The five-point map consists of five successive OFF-ON-ON-OFF sequences (continuum and beam-switched spectral line), or five successive ON and OFF measurements (position-switched spectral line), or five successive ON measurements with one…

4.6.2_pointing_model_equations

2007-06-19T06:31:51-07:00

4.6.2 Pointing Model Equations In addition to coordinate conversions, the telescope tracking program incorporates pointing corrections. The pointing corrections take into account such factors as resolver zero offsets, differences between electrical and mechanical axes, and axis tilt. The coefficients of the pointing model equations are determined during dedicated optical and radio pointing source measurements several times during the observing season. The pointing models used for the 12m ar…

4.6.3_pointing_data_analysis_program

2007-06-19T07:00:49-07:00

4.6.3 Pointing Data Analysis Program Each time a continuum five-point measurement is made, the online data server performs a fit to the results and writes them to a permanent file for later analysis. A program called Xgpoint is available on any of the mountain workstations for display and analysis of the recent pointing history of the telescope.

4.6_pointing

2007-06-26T07:19:48-07:00

4.6 Pointing You are responsible for determining the residual azimuth and elevation pointing offsets, relative to the nominal telescope pointing. These offsets are usually on the order of 0” to 20” and often vary across the sky. In particular, the offsets often show an elevation-dependence. The pointing of the 12m may drift over a period of several months by 10” or so, and you are cautioned not to assume that old pointing data are still valid. If a project requires accurate pointing, obser…

4.7.1_axial_focus

2006-09-18T10:09:23-07:00

4.7.1 Axial Focus To bring the incident radiation to a focus at the receiver feed horn, the subreflector of the 12m may be moved in and out along the electrical axis of the telescope. The focus exhibits an elevation-dependence which is automatically corrected by the control system computer, according to the equation

4.7.2_determining_the_axial_focus

2007-06-19T07:14:07-07:00

4.7.2 Determining the Axial Focus The axial focus of the telescope should be checked occasionally during an observing run. It is often most convenient to do a focus check after a continuum five-point pointing measurement since both measurements use the same kinds of sources (strong continuum point sources). It is particularly important to check the focus after nightfall and daybreak.

4.7.3_lateral_focus

2007-06-19T07:15:37-07:00

4.7.3 Lateral Focus The position of the subreflector for optimum gain shifts in the elevation direction, with changing elevation angle. The change in antenna gain produced by this effect is not significant at 3 mm wavelengths but could be relevant at 2 mm and shorter wavelengths. The 12m is equipped with lateral “north-south” and “east-west” translation stages at the prime focus to eliminate this loss in antenna gain. The computer is able to control automatically the positioning of these st…

4.7_focus

2006-07-20T13:23:29-07:00

4.7 Focus * 4.7.1 Axial Focus * 4.7.2 Determining the Axial Focus * 4.7.3 Lateral Focus Up12 Meter Observers ManualPrev4.6.3 Pointing Data Analysis ProgramNext4.7.1 Axial Focus

4_analysing_otf_data

2006-09-21T10:22:55-07:00

* 4.1 Analysing OTF Data in UniPOPS * 4.2 Analysing OTF Data in CLASS * 4.3 Analysing OTF Data in AIPS UpOn The Fly ObservingPrev3.2 DatabrowseNext4.1 Analysing OTF Data in UniPOPS

4_tracking_pointing_and_focus

2006-07-20T13:03:52-07:00

Chapter 4: Tracking, Pointing, and Focus * 4.1 Tracking Capabilities * 4.1.1 Sidereal Objects * 4.1.2 Ephemeris Objects * 4.2 Tracking Limits * 4.2.1 Elevation Limits * 4.2.2 Azimuth Limits * 4.3 Tracking Error Tolerance * 4.4 Sequence of Position Computation Operations * 4.5 Subreflector Beam Throw * 4.6 Pointing * 4.6.1 Continuum and Spectral Line Five-Point Measurements * 4.6.1.1 Continuum Five-Point Analysis in UniPOPS * 4.6.1.2 Spectral Line Five-Point …

4_tuning_the_frequency

2006-08-14T12:55:38-07:00

Now you've HARMed the frequency and locked the gunns on both channels. It is time to tune the frequency. The exact steps depend on the band you're in. Up12 Meter Operators ManualPrev3 Locking the GunnNext4.1 Tuning a Frequency on the 3mmhi Band

5.1.1_filterbank_software_changes

2006-08-15T06:28:30-07:00

5.1.1 Filterbank Software Changes First, open the Filterbank Setup screen (Figure 5.1) from RAMBO Utilities. Figure 5.1 Filterbank Setup Screen Select the observer's desired filterbanks by clicking on the given bandwidths and the configuration of the two channels (parallel or series) for each filterbank. The setup shown in Figure 5.1 is for 500p/1000p. Select Reset FB Setup.

5.1.2_filterbank_hardware_changes

2006-08-15T06:39:40-07:00

5.1.2 Filterbank Hardware Changes Second, go to the FB chassis in the Computer Room. Using the small cables provided, connect the IF Outputs to the FB Inputs by following a few simple rules. 1. The 2-MHz FBs (blue) are always connected to the 342-MHz IFs (red).

5.1_filterbanks

2006-08-15T06:25:02-07:00

5.1 Filterbanks To set up the FBs, you need to use the software AND make manual changes to the controls in the Computer Room. Up12 Meter Operators ManualPrev5 Setting up the BackendsNext5.1.1 Filterbank Software Changes

5.1_startup_checklist

2007-06-19T07:25:23-07:00

5.1 Startup Checklist Once the scientific goals of the observing session have been clearly established, you must decide which equipment and observing techniques you will use. The decisions to be made and the available options are listed below.

5.2_mac

2006-08-15T07:02:19-07:00

5.2 MAC To set up the MAC, you only need to make software adjustments. (Hardware adjustments are reserved for when things aren't working. See 12m Troubleshooting Guide for Troubleshooting tips.) You need to adjust two screens to configure the MAC.

5.2_sideband_choice

2007-06-19T08:32:39-07:00

5.2 Sideband Choice All of the 12m receivers operate by default in a single sideband (SSB) mode. It is possible to operate in DSB mode, but as discussed in §5.1, this is not recommended. Equipment constraints, such as the tuning range of the local oscillator or the receiver, may sometimes determine the sideband used in DSB mode. Other times, the presence of terrestrial lines steer the choice (see Figure 6.1). When using DSB mode, make the sideband choice with care.

5.3.1.1_the_parallel_series_option

2007-06-19T08:43:26-07:00

5.3.1.1 The Parallel/Series Option Most of the 256-channel FBs can be split into two 128-channel sections that can be fed with independent IF signals. When an FB is split into two sections, the FB is said to be in a parallel configuration. Each polarization channel of the receiver feeds half of an FB in this configuration. The advantage of this mode is that the two halves of the FB can be averaged to produce improved signal-to-noise in the final spectrum. The disadvantage of this mode is…

5.3.1.2_bad_channel_elimination

2007-06-19T08:53:11-07:00

5.3.1.2 Bad Channel Elimination At times, certain channels in the filterbanks are defective. You can identify these bad channels by examining a scan. Bad filter channels usually appear as spikes in the spectrum and will often cause scaling problems if not eliminated.

5.3.1.3_frequency_offsets

2007-06-19T08:54:55-07:00

5.3.1.3 Frequency Offsets Given the broad-band tunability of the 12m receivers, one can shift the rest frequency measured by the FBs by specifying a frequency offset to be added to the rest frequency. Offsets as large as the entire bandwidth of the receiver (±300 MHz) are possible.

5.3.1_filterbanks

2007-06-26T07:55:00-07:00

5.3.1 Filterbanks The analog filterbanks (FB) have 256 channels each, except for the 30-kHz FB, which has 128 channels. The filters are integrated, multiplexed, and recorded by the control computer every 100 ms. A total of 512 channels can be recorded at a time, which means that two FBs can be used for each scan. The filter spectrometers available and the ways in which they can be configured are described below. Table 5.1 lists the characteristics of the 12m filterbanks.

5.3.2_millimeter_autocorrelator

2007-06-19T09:01:20-07:00

5.3.2 Millimeter Autocorrelator The Millimeter Autocorrelator (MAC) offers a number of bandwidth and resolution modes, listed in Table 5.2. Table 5.2: MAC Configurations Shorthand⊕Total Bandwidth Usable Bandwidth†Resolution‡ [kHz] Frequency [MHz]Channels Frequency [MHz]Channels Sample IntervalFWHM 600-2k-2 800 2048 600 1536 390.6 781.2 600-4k-2 800 4096 600 30…

5.3_spectrometers

2006-09-18T10:18:05-07:00

5.3 Spectrometers Two spectrometer systems are available at the 12m: a suite of analog filterbanks and a MAC, which is a digital correlation spectrometer. Up12 Meter Observers ManualPrev5.2 Sideband ChoiceNext5.3.1 Filterbanks

5.4.1_total_power_ons_and_offs

2007-06-19T09:08:30-07:00

5.4.1 Total Power ONs and OFFs Two observing procedures, called tpon and tpoff, are available for recording total power spectral line scans. The two procedures are identical, except that tpon tracks the ON (source) position and tpoff tracks the OFF (reference) position. You must execute the procedures manually, one scan at a time. As such, these procedures are mainly used for diagnostic purposes. To use tpoff and tpon, follow these directions:

5.4.2_position_switching

2007-06-19T09:15:21-07:00

5.4.2 Position Switching Position switching, called the PS mode, is the most common and reliable observing mode at the 12m for general spectral line observations. It involves considerable overhead in telescope movement and requires that equal time be spent in the ON and OFF source positions, but the data quality is usually very good. In this mode, the telescope moves between the ON position and a relative OFF position, which may be specified in either azimuth and elevation, or right ascensio…

5.4.3_absolute_position_switching

2007-06-19T09:18:34-07:00

5.4.3 Absolute Position Switching Absolute position switching, called the APS mode, is a specific case of PS mode observing. It is useful when observing in complex emission regions where it may be difficult to find an emission-free reference position. In such cases, position switching with (AZ, EL) offsets can be dangerous because rotation of the parallactic angle as the source is tracked across the sky may cause emission to rotate into and out of the reference beam. You will want to search…

5.4.4_frequency_switching

2007-06-26T07:58:53-07:00

5.4.4 Frequency Switching The frequency switching (FS) observing mode has two primary uses: to increase the on-source integration time through in-band switching and to alleviate the problem of finding an emission-free reference position when observing in a (spatially) complex emission region. It also entails less system overhead than most other observing modes. In this mode, a reference spectrum is obtained by shifting the center frequency of the signal spectrum. In principle, this can be d…

5.4.5_beam_switching

2007-06-19T09:56:17-07:00

5.4.5 Beam Switching Spectral line beam switching can be useful when observing small angular diameter sources and when the best possible baselines are needed. This observing mode involves the nutation (chopping) of the subreflector and a positional movement of the telescope and is thus called the BSP (beam switching plus position switching) mode. The technique is much the same as that used for continuum ON/OFF's (see §6.4.1 and Figure 6.2). With the subreflector nutating at a rate typically…

5.4.6.1_manual_offsets

2007-06-19T10:38:14-07:00

5.4.6.1 Manual Offsets Often an observer will want to make a simple source map consisting of only a few points. In such cases, manual offsets (in RA, DEC) from the center position are the easiest way to proceed. Follow these steps: * Enter the center position into a source catalog. * Compute the offsets in angular units.† * Repeat Step 2 for as many positions as you like

5.4.6.2_grid_mapping

2007-06-19T10:42:24-07:00

5.4.6.2 Grid Mapping In the grid mapping modes, you can define a rectangular [RA, DEC] or [lII, bII] grid with different grid spacing in the horizontal and vertical coordinates. You can also define a grid to be acquired at an arbitrary rotation angle. The number of rows and columns must be an odd number.

5.4.6.3_otf_mapping

2007-06-19T10:40:51-07:00

5.4.6.3 OTF Mapping See the manual, On The Fly Observing, for an in-depth discussion of OTF Mapping. Up12 Meter Observers ManualPrev5.4.6.2 Grid MappingNext5.5 Spectral Line Sensitivities

5.4.6.3_what_type_of_mapping_should_i_do

2006-09-18T10:43:59-07:00

5.4.6.3 What Type of Mapping Should I Do? As a general rule-of-thumb, it is best to use OTF mapping instead of the step-and-integrate mapping described in this section when your map field is larger than about 6 ' in either RA or DEC and your target spectral line is expected to be reasonably strong.

5.4.6_mapping

2007-06-19T10:41:57-07:00

5.4.6 Mapping The 12m system offers three modes of spectral line mapping: * Mapping by manual offsets: good when observing a small number of positions offset from center * Grid mapping: good when the signal line is weak and the area to be covered is small (i.e. less than about 6' by 6') * On-The-Fly mapping: good when the signal line is strong and the area to be covered is large (i.e. greater than about 6' by 6').

5.4_observing_modes

2006-09-14T09:50:01-07:00

5.4 Observing Modes There are six primary spectral line observing modes available at the 12m. The attributes and applications of each are described in detail below. Signal processing and calibration for each mode are described in §5.6. Up12 Meter Observers ManualPrev5.3.2 Millimeter AutocorrelatorNext5.4.1 Total Power ONs and OFFs

5.5_spectral_line_sensitivities

2007-06-26T08:00:50-07:00

5.5 Spectral Line Sensitivities The spectral line calibration technique generally used at the 12m is the vane method. The effective system temperature given by this technique includes corrections for atmospheric attenuation, antenna spillover, blockage, and ohmic losses. The method does not include a correction for error pattern losses as the error beam will couple differently to different sources. The effective system temperature, Tsys, on the scale defined above, is given by

5.6.1_vane_calibration

2007-06-26T08:02:03-07:00

5.6.1 Vane Calibration The calibration mode used for almost all spectral line observations at the 12m is the vane method. In this method, a calibration signal is generated by differencing the signals recorded first on cold sky and then on an ambient temperature absorber. A vane is a paddle covered with microwave absorber that is switched in and out of the beam at a rate of about 1 Hz. A chopper wheel is a chopping blade whose solid portions are covered with absorber and which rotates at a r…

5.6.2_direct_calibration

2006-07-26T10:06:13-07:00

5.6.2 Direct Calibration Direct calibration is no longer in use at the 12m. Up12 Meter Observers ManualPrev5.6.1 Vane CalibrationNext5.7 Signal Processing

5.6_calibration

2006-07-26T09:50:49-07:00

5.6 Calibration * 5.6.1 Vane Calibration * 5.6.2 Direct Calibration Up12 Meter Observers ManualPrev5.5 Spectral Line SensitivitiesNext5.6.1 Vane Calibration

5.7.1.1_vane_chopper_calibrates

2007-06-26T08:02:28-07:00

5.7.1.1 Vane/Chopper Calibrates When a vane calibration is performed, a calibration array called the gains array is computed according to the formula [5.9] where Ci = effective system temperature for channel i, SCi = calibration signal (vane over the feed) for channel i, RCi = calibration reference (cold sky) for channel i, Zi = zero value response of channel i with no input signal, and TC is the calibration scale temperature.

5.7.1.2_no-cal_signal_processing

2007-06-26T08:02:41-07:00

5.7.1.2 No-Cal Signal Processing In the no-cal mode, the antenna temperatures are calculated by [5.12] where = zenith optical depth (called TAU0 in the control system), and A = airmass, calculated as 1/sin(elevation). All other symbols are as defined in §5.7.1.1.

5.7.1_position_and_frequency_switched_data

2006-07-26T10:11:12-07:00

5.7.1 Position and Frequency Switched Data * 5.7.1.1 Vane/Chopper Calibrates * 5.7.1.2 No-Cal Signal Processing Up12 Meter Observers ManualPrev5.7 Signal ProcessingNext5.7.1.1 Vane/Chopper Calibrates

5.7.2_beam_switched_data

2007-06-26T08:03:00-07:00

5.7.2 Beam Switched Data Beam switched data are calibrated using the vane but the signal processing is different from position and frequency switching. When a calibrate is performed during a beam switching session, the gains array is defined as [5.13]

5.7_signal_processing

2006-07-26T10:09:59-07:00

5.7 Signal Processing * 5.7.1 Position and Frequency Switched Data * 5.7.1.1 Vane/Chopper Calibrates * 5.7.1.2 No-Cal Signal Processing * 5.7.2 Beam Switched Data Up12 Meter Observers ManualPrev5.6.2 Direct CalibrationNext5.7.1 Position and Frequency Switched Data

5.8_changing_the_intermediate_frequency

2007-06-26T08:03:22-07:00

5.8 Changing the Intermediate Frequency Occasionally a change in the Intermediate Frequency from the nominal 1.5 GHz is desirable. One example of this is when the program line is just outside the tuning range of the local oscillator. Another example is when, for double sideband observations, it is advantageous to observe lines from both the signal and image sidebands for pointing, calibration, or simultaneous line search purposes and the image line is just outside the normal spectral bandpas…

5.9_spectral_line_status_monitor

2007-06-19T13:25:13-07:00

5.9 Spectral Line Status Monitor The status monitor provides basic information about the status of the telescope and the observations that are underway. The observer should check the monitor frequently to see that the telescope and control system are configured as they should be.

5.9_spectral_line_status_screen

2007-06-27T07:27:26-07:00

5.9 Spectral Line Status Screen The status screen provides basic information about the status of the telescope and the observations that are underway. The observer should check the monitor frequently to see that the telescope and control system are configured as they should be.

5_off_scan_editing_utilities

2006-09-21T10:47:55-07:00

Tom Folkers has written a utility which allows one to modify the OFF measurement information in an OTF data set. The utility otfmakeoffs will synthesize an OFF measurement from the (presumably line-free) beginning and end of an OTF map. This utility writes its output files to the directory

5_setting_up_the_backends

2006-08-15T06:24:00-07:00

This section describes how to set up the backends: the filterbanks (FBs) and the Millimeter Auto Correlator (MAC). Up12 Meter Operators ManualPrev4.3 Tuning a Frequency on the 2mm BandNext5.1 Filterbanks

5_spectral_line_observing

2006-09-18T10:44:34-07:00

Chapter 5 Spectral Line Observing * 5.1 Startup Checklist * 5.2 Sideband Choice * 5.3 Spectrometers * 5.3.1 Filterbanks * 5.3.1.1 The Parallel/Series Option * 5.3.1.2 Bad Channel Elimination * 5.3.1.3 Frequency Offsets * 5.3.2 Millimeter Autocorrelator

6.1_pointing

2006-08-15T07:34:03-07:00

6.1 Pointing Open the Continuum 5-Point Map screen, Figure 6.3, from the Continuum Menu in RAMBO, Figure 6.4. Figure 6.3 Continuum 5-Point Map screen Figure 6.4 Continuum Menu in RAMBO Input values for all the fields. * The integration time per sample you choose depends on the strength of the source. Planets generally need between 2 and 5 s. Weaker sources need up to 10 s. * The remaining parameters are set to their default values. You shouldn't need to change them. * Grid spac…

6.1_startup_checklist

2007-06-20T08:01:43-07:00

6.1 Startup Checklist Once the scientific goals of the observing program are in mind, you must make the following decisions: Precise Observing Frequency: When choosing a precise frequency, consider both the absorption spectrum of the atmosphere and the possibility of contamination by galactic spectral line emission.

6.2_focusing

2006-08-15T07:37:26-07:00

6.2 Focusing Open the Continuum Axial Focus Check screen, Figure 6.7, from the Continuum Menu in RAMBO. Figure 6.7 Continuum Axial Focus Check screen Input values for all the fields. * The integration time per sample is generally the same as what you used in the 5-pt. * The remaining parameters are set to their default values. You shouldn't need to change them.

6.2_selecting_an_observing_frequency

2007-06-20T08:08:38-07:00

6.2 Selecting an Observing Frequency You should take some care in the precise choice of a continuum observing frequency. In addition to the scientific goals that determine the approximate frequency, you should also consider two other factors: which frequency gives the best atmospheric transmission, and whether the observations will be affected by contamination from spectral lines in the bandpass. In the 3-mm band, maximum transmission occurs near 90 GHz. Figure 6.1 is a plot of the atmosphe…

6.3.1_switching_modes

2007-06-20T08:18:38-07:00

6.3.1 Switching Modes In contrast to spectral line signals, continuum signals are fundamentally indistinguishable from other broadband noise sources, such as atmospheric emission, spillover radiation from the ground and surrounding buildings, and receiver gain fluctuations. Such noise sources (particularly atmospheric emission) are, in fact, usually stronger than the celestial signal. Furthermore, atmospheric emission may change over very short time scales (« 1 second) and may vary significa…

6.3.2_checking_the_subreflector_throw

2007-06-20T08:25:23-07:00

6.3.2 Checking the Subreflector Throw Suppose we are observing at 3mm and have set the subreflector for a nominal ±2'. In order to confirm this, have the operator do either a Continuum Az-El Grid Map or a Continuum Raster Scan on a bright source such as a planet.

6.3.3_continuum_sensitivity

2007-06-26T09:17:12-07:00

6.3.3 Continuum Sensitivity Continuum observations at the 12m are usually calibrated by a direct conversion of the measured antenna temperature into flux density measured in [Jy] where 1 Jy = 10-26W/m2Hz. The scaling requires that the observer determine the atmospheric zenith optical depth, usually done with a tipping measurement. For a point source, the conversion is given by the standard equation

6.3.4_the_digital_backend

2007-06-26T09:17:34-07:00

6.3.4 The Digital Backend The data from all standard continuum observations are processed through the digital backend (DBE). In §3.6.3 we gave a description of the hardware configuration of the DBE. It processes two independent channels and accumulates the signals from four switching phases, defined as:

6.3.5_software_signal_processing_of_digital_backend_data

2007-06-26T10:06:13-07:00

6.3.5 Software Signal Processing of Digital Backend Data The data sent from the control computer and recorded in the sdd file contain the four phases, integrated over the number of dumps, for each sample or sky position. Thus, the raw data scan contains four times as many points as there were samples. If the sample number is denoted by Si and phases in that sample as j, the data are recorded in the order

6.3_observing_basics

2006-07-26T12:14:04-07:00

6.3 Observing Basics You can perform several types of continuum observations at the 12m. The most common types are: * ON/OFF's – With the subreflector chopping, the telescope moves first to one beam position and then the other (appropriate for point source observations), * Grid Mapping – The telescope steps through a rectangular azimuth/elevation grid, and * On-The-Fly Mapping – Beam-switched data are acquired every 0.125 seconds while the telescope is driven continuously over a speci…

6.4.1_the_on_off_sequence

2007-06-20T09:11:40-07:00

6.4.1 The ON/OFF Sequence The 12m has available several observing procedures for making ON/OFF measurements, i.e., measurements of the difference between the output powers at a defined point (ON) and a nearby reference position (OFF). These procedures work whether or not the subreflector is nutating. The ON/OFF procedures are often used for measuring the flux density of weak point sources.

6.4.2.1_grid_mapping

2006-08-01T08:26:58-07:00

6.4.2.1 Grid Mapping In continuum grid mapping, a field is mapped in a rectangular grid in azimuth and elevation relative to the field center. This observing procedure was developed with the dual-beam restoration algorithm of Emerson, Klein, & Haslam (1979 Astr. Ap.,76, 92). It will, however, work satisfactorily for either fixed beam (total-power) mapping or the mapping of fields that are smaller than the subreflector throw via the +BEAM. Note that continuum OTF mapping is functionally the …

6.4.2.2_continuum_on-the-fly_mapping

2006-07-31T09:13:32-07:00

6.4.2.2 Continuum On-The-Fly Mapping The observing setup for continuum OTF mapping is very much the same as it is for spectral line OTF mapping. Continuum OTF data can be processed within. The routines in NRAO's Astronomical Image Processing System (AIPS) use the Emerson, Klein, & Haslam algorithm to restore the dual-beam switched map data. See the AIPS Cookbook chapter that describes continuum OTF data analysis for further information.

6.4.2_grid_mapping

2007-06-27T07:47:03-07:00

6.4.2 Grid Mapping In continuum grid mapping, a field is mapped in a rectangular grid in azimuth and elevation relative to the field center. This observing procedure was developed with the dual-beam restoration algorithm of Emerson, Klein, & Haslam (1979 Astr. Ap.,76, 92). It will, however, work satisfactorily for either fixed beam (total-power) mapping or the mapping of fields that are smaller than the subreflector throw via the +BEAM. Note that continuum OTF mapping is functionally the sa…

6.4.2_mapping_extended_sources

2006-07-31T09:00:32-07:00

6.4.2 Mapping Extended Sources Two options are available for mapping extended continuum sources: a grid-mapping procedure in which the telescope steps through a rectangular grid in the azimuth/elevation frame and On-The-Fly (OTF) mapping. For a detailed explanation regarding the pitfalls and perils of undersampling in mapping data, see On The Fly Observing.

6.4.3_continuum_on-the-fly_mapping

2007-06-20T09:08:00-07:00

6.4.3 Continuum On-the-Fly Mapping The observing setup for continuum OTF mapping is very much the same as it is for spectral line OTF mapping. See On The Fly Observing for more information. Up12 Meter Observers ManualPrev6.4.2 Grid MappingNext6.5 Sky Tip Procedures

6.4_observing_procedures

2007-06-20T09:03:07-07:00

6.4 Observing Procedures * 6.4.1 The ON/OFF Sequence * 6.4.2 Grid Mapping * 6.4.3 Continuum On-The-Fly Mapping Up12 Meter Observers ManualPrev6.3.5 Software Signal Processing of Digital Backend DataNext6.4.1 The ON/OFF Sequence

6.5.1_the_sptip_analysis_procedure

2007-06-27T09:45:04-07:00

6.5.1 The SPTIP Analysis Procedure The sptip data reduction procedure uses the difference between vane and sky temperatures to derive . This is the simplest of all the tip analysis routines: it requires no input parameters, it does not require accurate calibration of the temperature scale, and it nearly always produces at least a first-order approximation to the optical depth. It does, however, make a number of simplifying assumptions that may diminish its accuracy.

6.5.2_the_stip_reduction_procedure

2006-08-01T09:30:04-07:00

6.5.2 The STIP Reduction Procedure The stip reduction procedure fits Equation 6.14 to the data from an sptip observation by way of nonlinear least squares fitting. This procedure is the most direct of the two tipping analysis options: it makes no assumptions other than the accuracy of the basic model, Equation 6.11. To give an accurate measure of , it does have several stringent requirements:

6.5_sky_tip_procedures

2007-06-26T11:11:09-07:00

6.5 Sky Tip Procedures To calibrate continuum data properly, you must correct for the attenuation of the signal as it traverses the atmosphere. We usually determine the atmospheric attenuation from the optical depth at the zenith, . The total power antenna temperature at a given airmass (elevation) is a function of and is given by the equation:

6.6.1_vane_calibration

2006-09-18T11:20:05-07:00

6.6.1 Vane Calibration Calibration of the antenna temperature scale for continuum data is accomplished using the vane calibration technique (see §5.6.1). In addition to a calibration of the antenna temperature scale, absolute calibration of continuum data also requires a measurement of the aperture efficiency or a factor for converting from antenna temperature to flux density. It may also be necessary to apply a correction for the gain-elevation effect (depending on the particular observing …

6.6.2_hot_cold-load_calibration

2007-06-27T12:38:54-07:00

6.6.2 Hot/Cold-Load Calibration A hot/cold load calibration can be used to set the continuum temperature scale, to measure the receiver noise temperature, the noise tube temperature, the sky temperature, and the atmospheric optical depth. At present, we perform hot/cold loads by manually inserting hot and cold loads into the beam and measuring the deflections through the computer, on digital voltmeters, and sometimes on the analog chart recorders.

6.6.3_calibration_of_the_flux_density_scale

2007-06-26T11:23:15-07:00

6.6.3 Calibration of the Flux Density Scale For most continuum observations, the flux density scale is calibrated by observations of standard radio sources. In doing this, please remember that in addition to corrections for receiver and atmospheric effects you should allow for the gain-elevation properties of the telescope if the observations cover a significant range of elevations.

6.6_calibration

2007-06-20T09:20:12-07:00

6.6 Calibration To calibrate continuum data accurately, you must * set the temperature scale and/or flux density scale, * correct for atmospheric attenuation, and * correct for telescope systematics such as the gain-elevation effect. The method currently used to calibrate 12m continuum data is vane calibration.

6.7_continuum_status_monitor

2007-06-27T07:29:12-07:00

6.7 Continuum Status Monitor A sample continuum status monitor display is shown in Figure 6.7. Figure 6.7: Continuum status monitor display Each numbered box in Figure 6.7 indicates a section of the display describing a particular set of attributes for a continuum measurement.

6_continuum_observing

2007-06-20T06:29:09-07:00

* 6.1 Startup Checklist * 6.2 Selecting an Observing Frequency * 6.3 Observing Basics * 6.3.1 Switching Modes * 6.3.2 Checking the Subreflector Throw * 6.3.3 Continuum Sensitivity * 6.3.4 The Digital Backend * 6.3.5 Software Signal Processing of Digital Backend Data

6_pointing_and_focusing

2006-08-15T07:28:09-07:00

Now that you have tuned and configured the backends, you're ready to begin the formal part of the observations. Pointing and focusing are usually conducted at the start of a run and every one to two hours afterward. The observer will generally decide how often to point and focus. Typically you will do a point, then a focus, then one more point before beginning (or resuming) observations.

7.1.1_position_switching

2006-08-15T07:49:11-07:00

7.1.1 Position Switching In the case of PS, open the Pointing Offsets screen, Figure 7.3, from the Utilities menu in RAMBO, and set the Reference Offset in either Azimuth, Elevation, Right Ascension, Declination, Galactic Longitude, or Galactic Latitude, or in some combination thereof. The default is 30 ' in Az.

7.1.2_absolute_position_switching

2006-08-15T07:51:12-07:00

7.1.2 Absolute Position Switching In the case of APS, set the reference position in Catalog. This will be listed as another source in the user's catalog, usually the next line down. This is a typical catalog for APS observing. 17:59:49.50 -24:00:50.25 J2000.0 G05 -10.0 LSR RAD 18:01:43.00 -24:15:53.70 J2000.0 offG05 -10.0 LSR RAD 18:01:46.57 -23:47:51.61 J2000.0 G06 30.0 LSR RAD 18:00:26.17 -21:23:28.76 J2000.0 offG06 30.0 LSR RAD 1…

7.1_spectral_line_position_switching

2006-08-15T07:47:53-07:00

7.1 Spectral Line Position Switching Position Switching involves moving the telescope back and forth between the source (ON) and a relative OFF position, or in the case of Absolute Position Switching, an absolute OFF position. Open the Spectral Line Position Switching screen. The default values are as shown in Figure 7.2. The observer will tell you if s/he wants to change any of the values.

7.2_spectral_line_beam_position_switching

2006-08-15T07:53:40-07:00

7.2 Spectral Line Beam + Position Switching BSP Mode involves keeping the telescope tracking the source and using the subreflector to shift between ON and OFF positions. Open the Spectral Line Beam + Position Switching screen. The default values are as shown in Figure 7.4. The observer will tell you if s/he wants to change any of the values.

7.3_frequency_switching

2006-08-15T07:56:24-07:00

7.3 Frequency Switching FS Mode involves keeping the telescope tracking the source and shifting the frequency by a small amount: this allows the telescope to stay ON SOURCE throughout the observations thus reducing the overhead. Open the Spectral Line Frequency Switching screen. The default values are as shown in Figure 7.6. The observer will tell you if s/he wants to change any of the values.

7.4_grid_mapping

2006-08-15T08:00:47-07:00

7.4 Grid Mapping Grid mapping allows the observer to map a small extended region with good signal-to-noise ratios. Open the Spectral Line Grid Mapping screen. The default values are as shown in Figure 7.7. The observer will tell you if s/he wants to change any of the values.

7.5.1_setting_the_size_of_the_otf_map

2006-08-15T08:27:21-07:00

7.5.1 Setting the size of the OTF Map When setting the size of the OTF Map, please note the following: * Row Spacing is calculated automatically as a function of frequency * Map Size in RA can be entered directly * Map Size in DEC has to be forced by entering the number of rows and hitting Recalculate Vertical Map Size

7.5.2_using_the_mac_in_an_otf_map

2006-08-17T09:01:26-07:00

7.5.2 Using the MAC in an OTF Map Don't use the MAC in an OTF map. RTData will crash if you do. If you absolutely have to use the MAC, reduce the number of channels in use to ~512. Up12 Meter Operators ManualPrev7.5.1 Setting the Size of the OTF MapNext7.5.3 Starting New Datafiles

7.5.3_starting_new_datafiles

2006-08-15T08:30:52-07:00

7.5.3 Starting new Datafiles As each map contains a lot of data, start a new datafile with every OTF map. Up12 Meter Operators ManualPrev7.5.2 Using the MAC in an OTF MapNext7.5.4 Reducing OTF Data in CLASS

7.5.4_reducing_otf_data_in_class

2006-08-15T08:33:28-07:00

7.5.4 Reducing OTF Data in CLASS Although the officially sanctioned data reduction program at the 12m is UniPOPS (a piece of software developed by the NRAO for single-dish telescopes), most visiting and remote astronomers use CLASS (a piece of software developed by IRAM for single-dish telescopes).

7.5_otf_mapping

2006-08-15T08:06:13-07:00

7.5 OTF Mapping OTF mapping allows the observer to map a large extended region in a relatively short period of time. Open the Spectral Line On-The-Fly Raster Map screen. The default values are as shown in Figure 7.7. The observer will tell you if s/he wants to change any of the values.

7_spectral_line_observing

2006-08-15T07:44:00-07:00

Move the telescope to the first source. The observer will likely want to do one (or more) of the following types of observation: * Position Switching (PS) or Absolute Position Switching (APS) * Beam + Position Switching (BSP) * Frequency Switching (FS) * Grid Mapping * On The Fly (OTF) Mapping

a.1_primary_pointing_equations

2007-06-28T11:09:16-07:00

A.1 Primary Pointing Equations The basic pointing model in use at the 12m is much the same as that described by Stumpff (1972, Kleinheubacher Berichte, 15, 431) and Ulich (1981, International Journal of Infrared & Millimeter Waves, 2, 293). The azimuth and elevation terms used to correct the nominal encoder positions are given by the equations,

a.2_secondary_pointing_corrections

2006-08-02T09:39:04-07:00

A.2 Secondary Pointing Corrections In addition to the primary pointing corrections, a set of secondary pointing corrections are used at the 12m. In azimuth, these corrections are given by the equation [A.9] where the left-hand side of the equation corresponds to the “cross-elevation” azimuth correction on the sky, given at a particular elevation by the observer-applied azimuth correction. In elevation, the secondary correction is

accessing_data_in_condar

2006-09-05T10:18:39-07:00

content UpUniPOPS DocumentationPrevStarting CondarNextReducing Data in Condar

accessing_data_in_line

2006-08-31T13:21:26-07:00

Most users only use one datafile during an entire observing season. If you're more prolific, and wish to access data from a previous datafile, type > chngver and select the datafile version you want. If you're in the middle of different data-access attempts, you may need to clear the index of scans and reset the backend type. For instance, suppose you just finished looking at MAC data for IRC+10216 and now you want to look at FB data for DR21(OH). You may need to type

aips_documentation

2007-06-18T07:18:25-07:00

AIPS is not applicable for the 12m. It is a program written by the NRAO, and is used for processing radio interferometric data. See their AIPS website here. UpARO WikiPrevCLASS DocumentationNextSMT Shutdown 2007

appendix_a_pointing_equations_for_the_12m_telescope

2006-08-02T07:25:31-07:00

* A.1 Primary Pointing Equations * A.2 Secondary Pointing Corrections Up12 Meter Observers ManualPrev6.7 Continuum Status MonitorNextA.1 Primary Pointing Equations

appendix_b_the_relationship_between_flux_and_brightness_temperature

2007-06-20T10:19:56-07:00

In the following we derive the relationship between the flux of a source and its brightness temperature for a gaussian beam, measuring two different source geometries: uniform disk and gaussian. The general relation between flux and brightness temperature is:

appendix_c_temperature_scales_and_telescope_efficiencies

2007-06-20T10:22:10-07:00

The calibration mode used for essentially all spectral line observations at the 12m is the chopper wheel method (see Ulich & Haas, 1976, ApJS, 30, 247 for a detailed description of this technique). The chopper wheel technique corrects for atmospheric attenuation and several telescope losses. In the following, we describe the temperature scale used at the 12m and how it relates to temperature scales used at other millimeter wavelength observatories.

appendix_d_spectral_resolution_and_sensitivity_bandwidth_in_spectrometers

2007-06-20T10:29:36-07:00

For many of the spectrometers used at millimeter-wavelength observatories (e.g. filterbank spectrometers and correlation spectrometers), the true bandwidth of a single spectrometer channel is a convolution of the original gain response of the channel and any smoothing functions applied. This convolution of the response and smoothing functions affects two important factors

appendix_e_walsh_function_modulation

2006-09-20T07:33:03-07:00

All observations that involve position switching or focus modulation (which is usually only done with frequency switching measurements) at the 12 Meter Telescope use a Walsh function for each SIG–REF measurement. For a given measurement of duration, P, composed of n SIG–REF measurement pairs (a SIG–REF pair is referred to a “repeat” in the 12m telescope lingo), a switching sequence determined by the Walsh function of PALey order 2n–1 is built up. Building up a PALey order of 2n–1 Walsh functio…

appendix_f_the_radiometer_equation_for_position_switched_measurements

2007-06-20T10:38:42-07:00

Given, [F.1] [F.2] [F.3] [F.4] [F.5] we can calculate as follows: [F.6] where we have neglected terms quadratic in . Noting that, [F.7] we see that [F.7] and [F.6] differ only by a constant (which is the volt-to-temperature scaling factor). Therefore,

appendix_g_the_12m_telescope_primary_focus_plate_scale

2006-08-07T11:10:26-07:00

The primary focus plate scale, which determines the amount of beam displacement as a function of lateral displacement of the subreflector, is given by, [G.1] where, = beam deviation on the sky, F( r ) = receiver feed illumination pattern, and f = primary focal length.

aro

2006-08-07T09:16:00-07:00

* ARO Wiki

aro_documentation

2006-09-11T10:33:30-07:00

Please Note: With few exceptions, these pages are only accessible by Steward Observatory Computers. * 12 Meter Documents * SMT Documents * Internal Documents UpARO WikiPrev12 Meter DocumentationNextRemote Observing at the ARO

aro_specific_usage_of_unipops

2006-05-17T16:05:54-07:00

aro_wiki

2007-06-18T07:17:18-07:00

* [MGIO Emergency Response Contingency Plan] * [KPNO Emergency Manual] * SMT Documentation * 12 Meter Documentation * ARO Documentation * Remote Observing at the ARO * Sun Avoidance Information * Using Orbital Elements for Ephemeris Objects * Proposal Submission Information

b.1_uniform_disk_source

2006-08-02T10:53:32-07:00

B.1 Uniform Disk Source For a uniform disc source, [B.2] From [B.1], this gives, [B.3] Let, [B.4] [B.5] Now we have, [B.6] If we let, [B.7] then we can integrate and substitute the variables, yielding our final solution,

b.2_elliptical_gaussian_source

2006-08-02T13:27:13-07:00

B.2 Elliptical Gaussian Source For an elliptical gaussian source, [B.9] Let, [B.10] and, [B.11] From [B.1] we have, [B.12] The solution to the double integral in [B.12] is, [B.13] Finally we can substitute the variables, yielding,

c.1_definitions

2007-06-20T10:23:37-07:00

C.1 Definitions In the following we define the terms used in the subsequent temperature scale and telescope efficiency discussion. we have tried to adopt a similar nomenclature to that used in Kutner & Ulich (1981, ApJ, 250, 341). Note that throughout this discussion when we refer to a temperature we are actually referring to the effective source radiation temperature J(,T), which is defined as:

c.2_relations_between_temperature_scales

2006-08-03T09:34:10-07:00

C.2 Relations Between Temperature Scales We can now combine the definitions above to derive the relations between the physical measurements and the temperature scale used at the 12m and the scales used at other telescopes. Combining the equations above, we can relate the source temperature corrected for atmospheric attenuation (T'A) to many of the antenna and source temperatures.

c.3.1_corrected_main_beam_efficiency

2007-06-20T10:27:49-07:00

C.3.1 Corrected Main Beam Efficiency The efficiency factor which converts the 12m T*R scale to the Tmb scale is given by: [C.21] Combining [C.21] with [C.14], [C.15] and [C.20] yields, [C.22] Given that, [C.23] [C.24] [C.25]

c.3.2_main_beam_efficiency

2006-08-07T06:53:27-07:00

C.3.2 Main Beam Efficiency The efficiency factor that converts any source antenna measurement to the Tmb scale is given by, [C.27] Up12 Meter Observers ManualPrevC.3.1 Corrected Main Beam EfficiencyNextAppendix D Spectral Resolution and Sensitivity Bandwidth in Spectrometers

c.3_telescope_efficiency_measurements

2006-08-03T09:47:44-07:00

C.3 Telescope Efficiency Measurements Telescope efficiencies are normally calculated using a measurement of the continuum brightness of a planet (for mb) or the Moon (for fss). In the following we give the relations used to calculate several telescope efficiencies. The source coupling between a disk source like the planets and a Gaussian telescope beam is given by:

class_documentation

2006-09-11T10:13:17-07:00

Here is a quick cheat sheet to get you started reducing 12m data in CLASS. * Converting OTF Data to CLASS * Reducing Data in CLASS UpARO WikiPrevUniPOPS DocumentationNextConverting OTF Data to CLASS

converting_otf_data_to_class

2007-06-20T11:08:07-07:00

Converting OTF Data to CLASS During the observing run, as you generate each OTF map, it is imperative that you record the following information: * first scan number for the map * last scan number for the map * datafile version for the map

current_telescope_status

2007-06-20T11:12:26-07:00

Telescope System Status Report The following contains up-to-date information on the telescope system. If there have been any recent failures in any of the telescope system components, they are reported here so that observers with pending observing programs can use this information to form their observing strategies.

d.1_sinc_function_integral

2006-08-07T08:03:33-07:00

D.1 Sinc Function Integral The sinc function integral is evaluated as follows: [D.6] Up12 Meter Observers ManualPrevAppendix D Spectral Resolution and Sensitivity Bandwidth in SpectrometersNextD.2 Gaussian Function Integral

d.2_gaussian_function_integral

2006-08-07T08:05:24-07:00

D.2 Gaussian Function Integral The gaussian function integral is evaluated as follows: [D.7] Up12 Meter Observers ManualPrevD.1 Sinc Function IntegralNextD.3 Hanning Function Integral

d.3_hanning_function_integral

2006-08-07T08:09:10-07:00

D.3 Hanning Function Integral The Hanning function is non-zero only from –(N – 1) to N – 1, where N is the number of channels which are being smoothed. [D.8] Normally, we take 3 channels and give them weights 0.25, 0.5, and 0.25. Therefore, SB becomes,

d.4_hamming_function_integral

2006-08-07T08:11:14-07:00

D.4 Hamming Function Integral The Hamming function is just the Hanning function with different weighting. [D.10] Up12 Meter Observers ManualPrevD.3 Hanning Function IntegralNextAppendix E Walsh Function Modulation

dome_problems

2006-08-24T07:05:04-07:00

Consult this table for help troubleshooting dome problems. Up12 Meter Operators Troubleshooting GuidePrevEmergenciesNextFilterbank Problems

dsp_code

2006-06-01T17:20:05-07:00

Author: Tom Sargent, Steward Observatory Introduction This document describes the software that runs in the the Traquair HEPC2104 PC/104 DSP card. This is a PC/104 CPU card that is interfaced both to the A/D interfaces reading the outputs of the SMT shaft encoders and to the ISA bus of the “smtts” Linux host computer. So, the DSP is able to read the shaft encoder signals, compute the shaft rotation angles and report those shaft positions to the host Linux machine.

emergencies

2006-08-23T07:43:04-07:00

If there is an emergency at the 12m, such as illness, fire, or threatening weather, you must follow the directions in the Kitt Peak Emergency Manual. A hardcopy is available in the Control Room at the telescope. Please read it thoroughly and check the link above for updates.

filterbank_problems

2006-08-28T06:25:29-07:00

Consult this table for help troubleshooting filterbank problems. Up12 Meter Operators Troubleshooting GuidePrevDome ProblemsNextHardware Problems

hardware_problems

2006-08-24T07:47:05-07:00

Consult this table for help troubleshooting hardware problems. Up12 Meter Operators Troubleshooting GuidePrevFilterbank ProblemsNextMAC Problems

interactive_method

2006-08-31T11:15:35-07:00

Type > sod You are given a list of parameters to specify: 1. Object 2. Frequency 3. Scan # 4. Exit 5. Set to Default * Select 1 and enter the source name, e.g. IRC+10216. * Select 2 and enter the frequency range, e.g. 115 116. * Select 3 and enter the scan range: if you're not sure of the numbers or if you want every scan of that source at that frequency since the start of the datafile, enter 1 9999. * Select 4 and choose 1 for MAC data or 2 for filterbank data. * …

internal_documents

2006-09-06T12:41:16-07:00

* Office * Fax Machine * Copy Machine * US Robotics Modem in Tom's Office * Reports * [ARO Product Tree] * 12 Meter * SMT * ARO * Spectroscopy Lab * ARO Technical Approval * Use of Special Apparatus at ARO Facilities * Apparatus Donation Policy

kpno_web_site

2006-09-06T08:06:19-07:00

Please visit the KPNO Web Site for more information on Kitt Peak. Up12 Meter DocumentationPrev12 Meter TelescopeNextRoad Maps to Kitt Peak

mac_problems

2006-08-24T08:03:09-07:00

Consult this table for help troubleshooting dome problems. Up12 Meter Operators Troubleshooting GuidePrevHardware ProblemsNextMaintenance Issues

maintenance_issues

2006-08-24T08:39:35-07:00

Consult this table for help troubleshooting maintenance issues. this list Up12 Meter Operators Troubleshooting GuidePrevMAC ProblemsNextMonitor Errors

monitor_errors

2006-08-28T06:26:34-07:00

Consult this table for help troubleshooting monitor errors. Sun Avoidance Information Up12 Meter Operators Troubleshooting GuidePrevMaintenance IssuesNextNetwork and Computer Issues

network_and_computer_issues

2006-08-24T12:37:56-07:00

Consult this table for help troubleshooting network and computer issues. Up12 Meter Operators Troubleshooting GuidePrevMonitor ErrorsNextObserver Complaints

observer_complaints

2006-08-24T12:57:07-07:00

Consult this table for help troubleshooting problems brought to your attention by the observer. Sun Avoidance Information Up12 Meter Operators Troubleshooting GuidePrevNetwork and Computer IssuesNextPointing and Focus Trouble

on_the_fly_observing

2006-09-21T10:17:18-07:00

* 1 OTF Introduction * 1.1 When to OTF Map * 1.2 How OTF Observing Works * 1.3 An Important Note About Spatial Sampling * 1.4 Other Sources of Information * 2 Observing Setup * 2.1 OTF Observing Checklist * 2.2 OTF Map Parameters * 2.2.1 Row Sampling Rate * 2.2.2 Scanning Rate * 2.2.3 Row Length Limitations * 2.2.4 Bad Channel Flagging * 2.2.5 Map RMS * 2.2.6 Total Map Time * 2.2.7 Doppler Tracking

optical_pointing_instructions

2006-09-06T08:14:04-07:00

Follow these directions for optical pointing. * Set the observer initials to sys * Turn on camera: right switch up, left switch down * Start coptical on the optical pc: * > cd /home/corona/cactus/optical/pc * > ./coptical * You should see a hh:mm:ss> prompt, which indicates that the coptical program is ready for commands from the exec * Select the optical receiver from within Rambo * Go to pointing control screen and press (GO +BEAM) button, ensuring that the +/- beams are a…

paper-based_documentation

2006-09-06T08:12:27-07:00

If you're looking for a manual or paper that used to be in the Control Room but you can't find it, there's a good chance it was removed to the Laboratory for archiving. See the following table for more detailed information. Manuals FileVersion NumberDate UpdatedNumber of CopiesFateKitt Peak Emergency Manual6May 24, 20051Control RoomSMTO User's Manual6.5May 1, 20021Control RoomKitt Peak Safety ManualN/ANovember 19941Control RoomNRAO Phone BooksN/AObsolete2LabARO Phone ListN/APresent1Control…

pdfs

2006-09-18T09:06:44-07:00

Here is the directory of the 12 Meter Observers Manual in PDF format, listed by chapter and last updated November 2004. * [Cover Page] * [Preface Page] * [Table of Contents] * [Chapter 1: Introduction] * [Chapter 2: Getting Started] * [Chapter 3: Instrumentation] * [Chapter 4: Tracking, Pointing and Focus] * [Chapter 5: Spectral Line Observing] * [Chapter 6: Continuum Observing] * [Appendix A: Pointing Equations for the 12m Telescope] * [Appendix B: The Relationship Betwe…

planetary_nebulae

2008-04-22T10:27:56-07:00

One of the areas of major focus at the ARO facilities has been the study of physical and chemical properties of evolved stars. Hrivnak and Bieging (2005), for example, have used the SMT to measure the J=2->1(230 Ghz) and J=4->3(460GHz) transitions of CO towards a sample of 22 protoplanetary nebulae. Modeling of these data has shown that the stellar envelope density is much steeper than r-2, implying a sharp increase in mass loss as the stars evolve on the AGB. The data yield the quantitative tim…

pointing_and_focus_trouble

2006-08-28T07:34:52-07:00

Consult this table for help troubleshooting pointing and focus problems. Up12 Meter Operators Troubleshooting GuidePrevObserver ComplaintsNextPower Trouble

power_trouble

2006-08-28T08:24:12-07:00

Consult this table for help troubleshooting power problems. Up12 Meter Operators Troubleshooting GuidePrevPointing and Focus TroubleNextReceiver Problems

preface

2006-09-13T07:57:01-07:00

This manual is a general reference guide for the operation of the Arizona Radio Observatory (ARO) 12m millimeter-wave telescope. We have included basic material required for first-time use of the telescope, as well as more detailed information of interest to all observers.

proposal_submission_information

2006-09-13T08:26:55-07:00

The Arizona Radio Observatory (ARO) is accepting observing proposals for use of the Submillimeter Telescope (SMT) on Mt. Graham, Arizona and for the Kitt Peak 12 Meter Telescope (KP12m) for the period January 1, 2007 - March 31, 2007. The telescopes are expected to be available to the general astronomical community for a minimum of 10 percent of the scheduled time. Graduate student participation is especially encouraged regardless of institutional affiliation. Institutions (or individuals) wi…

receiver_problems

2006-08-28T09:05:56-07:00

Consult this table for help troubleshooting receiver problems. Up12 Meter Operators Troubleshooting GuidePrevPower TroubleNextRuntime Errors

reducing_class_data_at_the_smt

2006-09-18T08:59:42-07:00

Theresa, please consult CLASS Documentation and create similar documentation for SMT CLASS Data reduction. Thanks. erin UpARO WikiPrevSMT Proposal PageNext[SMT Room Schedule]

reducing_data_in_class

2007-06-18T09:59:06-07:00

Reducing Data in CLASS NB. This page was created with the 12m data in mind. Consult Reducing CLASS Data at the SMT for a page forcused on SMT data. Feel free to test out these commands using the file /home/obs/sampleclass.12m, being sure to copy it to your own directory before playing with it.

reducing_data_in_condar

2006-09-05T10:19:50-07:00

content UpUniPOPS DocumentationPrevAccessing Data in CondarNextSaving Files in Condar

reducing_data_in_line

2006-09-12T06:33:28-07:00

Once you've added all the data for a given source, frequency, offset position and backend setup to your stack, either through the interactive or user-defined method, you're ready to begin reducing them. If your data contain bad channels you can remove them as follows. Type

remote_observing

2006-07-24T12:41:38-07:00

NOTE TO SELF: Make this pretty. Original content: Look here for late breaking news that affects remote observing. Welcome to ARO Remote Observing. With the completion of the new control system on the HHT 10 Meter telescope, ARO can now offer remote observing to the radio astronomy community using both telescopes. The 10 Meter now joins the 12 Meter’s rich history of providing world class remote observing.

remote_observing_at_the_aro

2008-04-22T10:30:31-07:00

The ARO now offers world-class remote observing at both the 12m and the SMT. Observers can connect to the 12m or SMT computers and * establish a remote data reduction session, * see the on‑line Status screen, * have a computer Talk session with the telescope operator, * have a real‑time automatic display of incoming data, * browse previously recorded data, * see weather information, and * view receiver switched power and total power chart recorder output.

road_maps_to_kitt_peak

2007-06-20T11:05:18-07:00

From the Steward Observatory at the University of Arizona, take Cherry Ave North to Speedway Blvd. Take Speedway Blvd West to I-10. Take I-10 SouthEast to I-19. Take I-19 South to Ajo Way. Take Ajo Way West until it turns into Highway 86 and keep going West.

runtime_errors

2006-08-28T09:47:11-07:00

Consult this table for help troubleshooting runtime errors. windyazimuth or elevation trackingwind Up12 Meter Operators Troubleshooting GuidePrevReceiver ProblemsNextTracking Problems

saving_files_in_condar

2006-09-05T10:20:50-07:00

content UpUniPOPS DocumentationPrevReducing Data in CondarNextCLASS Documentation

saving_files_in_line

2006-09-12T10:51:54-07:00

science_at_the_smt

2006-09-05T06:34:28-07:00

* Planetary Nebulae UpSMT DocumentationPrevSMT Control SystemNextSMT Proposal Page

servo.c

2006-06-01T17:09:22-07:00

Author: Tom Sargent Introduction: The servo.c program resides on the “smtots” Linux-hosted computer. This machine has PC104 interfaces to the Traquair (Hunt) HEPC2104 DSP processor which in turn has the A/D interfaces which read the outputs of the SMT shaft encoders. Every 10ms (nominally) the DSP processor sends a position report to the smtots computer which the servo.c program reads. The smtots machine also has ISA bus parallel I/O ports and other A/D and D/A interfaces which interface…

smt_control_system

2006-09-05T06:33:40-07:00

* Tracker Servo UpSMT DocumentationPrevSMT Observers ManualNextScience at the SMT

smt_documentation

2006-09-18T08:55:10-07:00

* SMT Operators Manual * SMT Observers Manual * SMT Control System * Science at the SMT * SMT Proposal Page * Reducing CLASS Data at the SMT * [SMT Room Schedule] UpARO WikiNext12 Meter Documentation

smt_documents

2006-09-06T11:06:06-07:00

* Frontends * 1.3-2mmJT * Computer Control * Diamond Systems * Hercules-EBX Mother Board * [Manual] * Ruby DAC RMM-1612-XT Rev A * [Manual] * Universal Driver Software V5.7 * [User Guide] * [CPU Power Supply Wiring Diagram]

smt_observers_manual

2006-09-05T06:33:04-07:00

content UpSMT DocumentationPrevSMT Operators ManualNextSMT Control System

smt_operators_manual

2007-05-09T03:08:11-07:00

Chapter 1: Introduction For Telescope Operators * 1.1 So You Wanna Be a Telescope Operator? * 1.2 Telescope Operator Duties * 1.3 Operator Shift Schedule * 1.4 Observing Schedule * 1.5 The SMT Building * 1.6 MGIO, UAPD, On Site Policies and Help * 1.7 SMT Observers * 1.8 Other Mt. Graham Information

smt_proposal_page

2006-09-18T08:56:46-07:00

content UpSMT DocumentationPrevScience at the SMTNextReducing CLASS Data at the SMT

smt_shutdown_2006

2007-06-18T07:17:50-07:00

Building Job Who? Priority Done Rebuild the gas powered hydraulic pump/engine. SB 1 At Repair Shop Hydraulic service SB 1 X Clean track. All 1 Adjust building wheels SB 1 In Tolerance Crane maintenance SB 1 Investigate stink detector to find sewer smell source. RM TJ 1 X Get manufacturer to adjust Building Drives and to train staff to do this. TF 1 canx Door and roof limit switches SB RM 1 Check li…

so_you_wanna_be_a_telescope_operator

2006-07-13T10:58:07-07:00

Congratulations you are about to embark on a fascinating and exciting journey that is submillimeter wavelength radio astronomy! This manual is designed for the novice to advanced telescope operator of radio astronomy. Most of our operator positions have a high turn around and usually have no real radio background whatsoever. Make sure you know what scope you are working for. Arizona Radio Observatory (ARO) has two radio telescopes on different mountain tops. This manual is intended for the 10m…

starting_condar

2006-09-05T10:14:25-07:00

Once you’ve typed condar from your observer directory, you will see the following on your screen Version: 41004. USAGE: = name of root directory of messages = name of log file; logs the last time messages were read News Items ---------------- Local-Global-Symbols V3.1_Changes V3.3_Changes V3.4.1_Changes V3.4_Changes V3.5_Changes V3.6_Changes ---------------- Enter the name of the item you want t…

starting_line

2006-09-11T07:41:39-07:00

Once you've typed line from your observer directory, you will see the following on your screen Version: 41004. USAGE: = name of root directory of messages = name of log file; logs the last time messages were read News Items ---------------- Local-Global-Symbols V3.1_Changes V3.3_Changes V3.4.1_Changes V3.4_Changes V3.5_Changes V3.6_Changes ---------------- Enter the name of the item you want to …

sun_avoidance_information

2006-09-11T10:33:07-07:00

To avoid excessive heating of the feed legs, the prime focus regions, and the cables of the prime focus, the SMT telescope will not be pointed to within 42 degrees of the sun, and the 12 Meter, 15 degrees. The following table lists the apparent RA and Dec of the Sun on the first of each month (we have ignored the small year-to-year changes due to precession). Observers are encouraged to use this information to specify their proposal requests for observing time.

tracker_servo

2006-06-01T15:55:08-07:00

* DSP Card * Servo API * Servo.c * DSP Code

tracking_problems

2006-08-28T10:32:46-07:00

Consult this table for help troubleshooting tracking problems. Up12 Meter Operators Troubleshooting GuidePrevRuntime ErrorsNextTuning Problems

tuning_problems

2006-08-29T06:34:36-07:00

Consult this table to help troubleshoot Tuning Problems. 3 Locking the Gunn2.2 Switching the Optics Up12 Meter Operators Troubleshooting GuidePrevTracking ProblemsNextWeather Trouble

unipops_continuum_data_reduction

2006-09-12T06:59:33-07:00

Condar is no longer available at the ARO 12m. UpUniPOPS DocumentationNextCLASS Documentation

unipops_documentation

2006-09-11T07:38:07-07:00

UniPOPS can be used to reduce both spectral and continuum data at the 12m. * UniPOPS Spectral Line Data Reduction * Starting Line * Accessing Data in Line * Interactive Method * User-Defined Method * Reducing Data in Line * Saving Files in Line

unipops_remote_printing_approach_2

2007-04-27T11:24:51-07:00

Unipops Remote Printing Approach 2 Overview This method * Requires some UNIX savvy, * May be a security issue for your remote host, * Can tie up the program while the graphics file is being printed, and * May not work if you are behind a firewall.

unipops_spectral_line_data_reduction

2006-09-11T07:37:24-07:00

UniPOPS Spectral Line Data Reduction If you're going to want to output postscript hardcopies of your data, then before starting line, type setenv popsprinter To reduce spectral line data using UniPOPS, type line at the prompt in modelo.

user-defined_method

2006-09-05T08:45:14-07:00

It is assumed that you've reviewed /home/obs/ini/operator.log to confirm that all the scans you select contain data for the same source, offset, backend configuration and frequency. To select a range of scans for consideration, type add(first_scan_num,last_scan_num) with the comma and without spaces. To add one scan at a time, type

using_orbital_elements_for_ephemeris_objects

2006-09-06T12:47:25-07:00

Using Orbital Elements for Ephemeris Objects Introduction: Orbital elements are specified in a file whose name ends with .eph in the /home/obs/ini directory, where ini is the observer's initials. The orbital elements should be calculated for (each) date of the observations. The length of time for which the elements are valid depends on the object and the nearest perturbers. A comet ephemeris is usually good enough for a week. A minor planet ephemeris generally lasts longer before it diver…

weather_trouble

2006-08-29T07:23:39-07:00

Consult this table for instructions during inclement weather. Up12 Meter Operators Troubleshooting GuidePrevTuning Problems