|Description||Proper motion and Parallax of Methanol Masers: A search for infalling gas|
|DAS Mode||vsop.pro (telescope)|
The beginning and end of the experiment will use the following setup
|Skyfreq IFP#1||6316.00 MHz|
|Skyfreq IFP#2||6657.00 MHz|
The purpose of these observations is to obtain a first epoch for proper motion/parallax observations of the methanol maser source G9.62+0.20. We are trialing a new observing mode where we will observe both masers and phase calibrators with 2×16 MHz bandpasses, but the correlator output will be high spectral resolution around the masers (G9.62+0.20 should show a strong peak at a sky frequency of around 6668.4 MHz during these observations) and standard continuum for the phase reference source. The idea is to have a mode which expands the number of suitable phase reference sources available for spectral line sources.
The experiment has 3 distinct sections, minor setup changes are required at 15:01:10 and 23:15:10 UT
During the ICRF runs we have sometimes had to exclude certain antennas (particularly Parkes) from observations of some sources in order to get a good spread of azimuths and elevations.
Cable up with the Huygens cable for the entire experiment. Observe with dual DAS setup using 2 DASes for the 4 x 16 MHz setups and 1 for the dual polarization 2 x 16 MHz setup. Record using the following cdisko channel selections at the appropriate time ranges. Stop the recorder in between! At Parkes you will have to change the frequency manually running for example (in a pavo xterm)
> lorun @2008_METH-split.cmd
|UT||Channel selection||Parkes Frequency setup|
ATCA will have to cacal at 6.3/6.7 GHz and 6.7/6.7 GHz.
The 4 x 16 MHz bandpass setup will require feeding two separate LOs into IFP#1 and #2 on the DAS/frequency translator and splitting the LCP signal so that is feed into both sides. For Hobart the LOs should be set to 468 MHz (IFP#1) and 809 MHz (IFP#2) for the 4 x 16 MHz setup and 809 MHz for the 2 x 16 MHz setup. For Ceduna, try setting the agilent to 11.1 GHz rather than 11.4 GHz, then you can use the same LOs as at Hobart.
Scheduled from 2150 - 2325 UT. The last source is after the change to the single polarization 4 x 16 MHz bandpass setup. Although all the other antennas should change, Hart should observe with the dual polarization 2 x 16 MHz bandpass setup.
During the fringe check we will need to calibrate the delay between the two ATNF DAS, and the delay between Hobart/Ceduna in dual pol and single pol mode. The following set of tests are suggested. Once fringes are found we will want at least 5min of data in each mode which is saved.
Everyone records with a dual polarisation/6.7 GHz setup. ATNF records at 512 Mbps (ie Huygens/Channel 1-8 in cdisko).
Hobart and Ceduna cable up with LCP into both IFP, but remain at 6.7 GHz. Pks/ATCA/Mop record chans 1-4.
Hobart and Ceduna retune IFP#1 to 6316 MHz. Pks/Mop/ATCA run with DAS#1 centred at 6316 and DAS#2 at 6657 MHz and record Chan 3,4,7,8 in cdisko.