KFPA Astrid Spectral Line Modes

Modification Request #? (C04 2009)


1. Introduction

The basic observing modes for the KFPA are similar to those already used by spectral line observers. This document specifies the addition of signal and reference beam(s) for KFPA observations. Our planed approach, for the near term, is to update the dual beam procedures for the KFPA use, by allowing the observer to explicitly select SIGNAL and REFERENCE beams.

2. Background

We have described KPFA pointing and focus plans for commissioning previously. The document describes re-configuration of the existing Astrid procedures and a new pointing mode to allow checking the relative gain of the 7 feeds.

3. Requirements

Astrid shall command spectral line observations with observer specified signal and reference beams. The spectral line procedures requiring updates are:

For brevity, we describe these procedures collectively as spectral line observations.

4. Design

A standard set of optional parameters should be added to all astrid procedures concerned with spectral line observations (as is done for point and focus observations. The parameters are the indexes to the beams to be used for different rolls in the peak and focus process. Since future procedures will allow different combinations of beams for different functions, below we suggest a general syntax for specifing all beams used in a particular process.

  • SIG=I, where I is index to one of beams in the array (range 1 to N) (ie SIG=1)
  • SIG=I,J,K,L, where I,J,K,L are indicies to beams in the array (ie SIG=1,2,3,4)
  • SIG=ALL, where ALL indicates all beams should be configured for the observations
  • REF=M, where M is the index of another of the beams for sky subtraction (ie REF=2)
  • REF=OTHERS, where OTHERS indicates all beams not in the SIG list.

The SIG and REF parameters are optional.

5. Example Usage

#Example Astrid script for an On-Off observation of TMC 
#HISTORY
# 09AUG26 GIL Initial version based on Single pixel test Astrid script

#First put in your sources
execfile("/home/astro-util/projects/TKFPA/sources.cat")

#configure for this frequency range
Configure("/home/astro-util/projects/TKFPA/configK200.py")

sourceName="TMCCP"                  
Slew(sourceName)                   # go to catalog location

Balance()                          # set IF/RF levels

#This break statement was a work-around to the use of C band Configuration
#for single pixel tests
Break("Remove C-band from scan-coordiantor: Converter Rack==11700")

#observe for total time per band
#This example commands tracking beam 2; 
#The configuration step (above) selects beams for use in the observation
OnOff( sourceName, Offset("J2000", 1.0, .0, cosv=True), 61.0, SIG=2)

Example of new sequence of calls to the revised OnOff routines.

6. Deployment Checklist

Steps in the deployment checklist.

7. Test Plan

7.1 Internal Testing

The software group must fill out this section This section covers things like unit testing, simulator testing, and any other tests required to make sure this MR is ready for sponsor/integration/regression testing.

7.2 Sponsor Testing

The sponsor testing for these procedures will be repeated execution of the modified procedures, listed above, for the procedures listed above. These test observations will be carried out in modest weather conditions, (neither perfectly clear nor rainy). Predicted zenith atmospheric tau should be in the range .05 to .1 The sponsor testing will include making spectral line observations with each beam of the array selected as the SIG beam and also each beam of the array selected as REF beam (but not all combinations (only 7 tests, not 7*6/2 = 21 observations).

7.3 Integration/Regression Tests

What do the integration/regression testers need to do in order to test this MR. Software Group will add this section

Signatures

APPROVED To the best of my knowledge, the request in this MR is complete. I have thought through this request, and believe it to be an important feature to implement or bug to fix.
ACCEPTED I acknowledge that I have validated the completed code according to the acceptance tests.

Written DONE - Glen Langston - 2009 August 26
Checked ALERT! - name - date
Approved by Sponsor ALERT! - name - date
Approved by CCC ALERT! - name - date
Accepted/Delivered by Sponsor ALERT! - name - date

Symbols: Use %X% if MR is not complete (will display ALERT!) Use %Y% if MR is complete (will display DONE)

CCC Discussion Area--

-- GlenLangston - 2009-08-26
Topic revision: r1 - 2009-08-26, GlenLangston
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