Interferometry in Interactive mode (Scheduling Block Execution) with software version 5.0.3

Author: 20080507 - AH

All sessions should be run on oper01.

In what follows:

  • > denotes the unix shell prompt,
  • >>> the python prompt,
  • CCL>>> the CCL prompt and
  • psi> the prompt for psi scripts.

To get the PSI prompt type:

>cd /groups/psi/Public_PSI

>./psi

.Prerequisites

The following assumes that the system has been set up (by the Operator) according to:

  1. Antenna Startup and Shutdown
  2. System Software Setup
  3. Radiometer Software Setup

This will ensure that the antennas are movable and in focus, with pointing models loaded, the receivers are set up, the line-length correction is turned on and being logged.

-1.Open Observing Log File and Report activities in the ATF Journal.

You must post your nightly activity in the ATF Activity Journal. The observed sources, SB/script used, and UID must be written down here, as this is the only way to keep track of what is being done every night. This is expected to be replaced soon by a proper logger system.

Optionally, You can also open the current month Log File for editing. Here you can add any log entries for the night, and also crucial information as UTC date, uid number and objects observed in each executed SB. It is a simple text file that can be edited in your preferred editor (e.g emacs, vi):

>cd /groups/sci/logs/

> emacs may.notes &

0.Run the logpower script

This utility will log total power data, az,el position and the hotload status and temperature from the specified antenna into an ASCII file in /groups/sci/interferometry/YYYYMMDD. Needed if you are planning to use the hot load for calibration.

>/groups/sci/scripts/5.0.2/logpower.py -a both -s 4

Will log data from both antennas, creating the YYYYMMDD directory if it does not already exist. Note that if the system crashes, logpower will halt and will need to be restarted.

1. Take a Skydip on both antennas to measure Receiver Temperature and Sky Opacity each night

(This should be run by the operators before the start of each night).

Execute the following script, which will run a SkyDip on both antennas. This command will write the Receiver Temperature and sky opacity to the SkyDipResults_yyyymmdd.txt file (Note that you need to edit the right yyyymmdd).

>cd /groups/sci/scripts/skydipData

For Vertex:

*> ./SkyDip503.py -a DV01 -p 0 | tee -a SkyDipResults_yyyymmdd.txt

For Alcatel:

*> ./SkyDip503.py -a DA41 -p 0 | tee -a SkyDipResults_yyyymmdd.txt

2 Run InterferometryTest in Manual Mode to check the system is fringing:

Create a Manual Array

On the OMC

View -> create array

This brings up a panel showing all potential antennas

Click Manual -> indicators for antennas 1 and 2 turn green

Left click on 1

Shift left click on 2

Both indicators should turn blue

Click on Create

Wait until the antennas are assigned to the array (click on Alma -> antennas; both antennas should be assigned to the new array CONTROL/Arraynnn).

Run the Interferometry Test Script in Manual Mode:

>mmc --arrayname=CONTROL/Arraynnn

where nnn is the number of the array you created in (3) - 001, 002, etc. This brings up the CCL prompt CCL>>>

Execute the InterferometryTest Script (*Check it has the right source for current LST, and correct cable delay, edit accordingly otherwise *):

CCL>>>execfile('/groups/sci/scripts/5.0.3/InterferometryTest.py')

In the OMC dataflow window, wait until the Scan number changes from 0-0 to 1-0. Once this has happened you can start the CorrGUI:

>CorrGUI

Here you should see fringes if everything is OK. Once the execution has ended, execute in the following order:

  1. Close the CorrGUI.
  2. Control-D the CCL shell
  3. In the OMC destroy the array

You can proceed to your observing now.

3. Set up a data directory

IF you have NOT run the logpower script and the data directory does not yet exist, create it:

>mkdir /groups/sci/interferometry/YYYYMMDD

where YYYYMMDD is the current UT date.

4. Create an array

On the OMC

View -> create array

This brings up a panel showing all potential antennas

Click Interactive -> indicators for antennas 1 and 2 turn green

Left click on 1

Shift left click on 2

Both indicators should turn blue

Click on Create

Wait until the antennas are assigned to the array (click on Alma -> antennas; both antennas should be assigned to the new array CONTROL/Arraynnn).

5. Create an Scheduling Block (SB)

Please refer to Creating an SB

The file /groups/sci/logs/ATF.xls contains a summary of existing SB. If you submit a new SB to the Archive, please add it to the excel file.

6. Check that the correlator is synchronised with the rest of the system

>ssh ccc

>arrayTimeCompare CORR/ARRAY_TIME/CDP_NODE/N01

>exit

You should see a line:

delta = remote-local: 0[acs]

If the number is NOT 0, then the correlator subsystem will have to be restarted and the correlator computers power cycled (see Appendix C).

7. Run your SB

In the OMC, go to the CONTROL/Arraynnn tab, and you will see the options for retrieving SBs from the Archive.

Select your project, select your SB and click execute. This will start the execution of the desired SB.

In the OMC dataflow window, *Write down the exec block id (which will be something like uid://X1eb/X2482/X1)*, as this is needed for data reduction. You will need to resize the field to see this. You will be able to see the progress of the observation in the scan and subscan fields. After the end of execution, the indicator on the left of the dataflow entry will be green, the numbers of completed scans and subscans should be as you set them in the script and control will be returned to the CCL prompt.

8. Exporting the data and making a measurement set

>cd /groups/sci/interferometry/YYYYMMDD

>asdmExport -b uid://X1eb/Xnnnn/X1

where nnnn is the number of the exec block noted earlier. This creates a directory uid___X1eb_Xnnnn_X1

>asdm2MS --ocm ca uid___X1eb_Xnnnn_X1

creates a measurement set called uid___X1eb_Xnnnn_X1.ms.

Now change permissions so that everyone can read/write it:

>chmod -R ugo+wrx uid___X1eb_Xnnnn_X1.ms

9. Plotting the data using CASA

Data reduction in CASA and LLC correction

10. Running a Skydip

#################################################

B2.On-line monitoring of the LLC for phase jumps

#################################################

To monitor LLC phase jumps visually, look at the LLC Labview displays on snickers. To get these, click on LLC1 -> details on the central lo rack display; similarly for LLC2. The frequency of phase jumps depends on the rate of ambient temperature change, and are more often on AEC due to the extra fibre length.

-- AntonioHales - 07 May 2008

This topic: ALMA > WebHome > AlmaSci > AlmImcal > ControNotesSB
Topic revision: 2008-05-23, AntonioHales
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