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:
- Antenna Startup and Shutdown
- System Software Setup
- 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:
- Close the CorrGUI.
- Control-D the CCL shell
- 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