|Description||Proper motion and Parallax of Methanol Masers: A search for infalling ga|
|Station Modes||At Cd Ho Mp Pa Sh|
|DAS 1 Skyfreq||6658 MHz|
|DAS Mode||vsop.pro (telescope)|
|Station Modes||At Cd Ho Mp Pa|
|DAS 1 Skyfreq||6316 & 6658 MHz|
|DAS Mode||vsop.pro (telescope)|
94 04:00:00 v255n.5cm
94 04:07:00 v255n.5cm-icrf
94 05:00:00 v255n.5cm
94 08:15:00 v255n.5cm-icrf
94 09:00:00 v255n.5cm
94 12:15:00 v255n.5cm-icrf
94 13:00:00 v255n.5cm
94 16:15:00 v255n.5cm-icrf
94 17:00:00 v255n.5cm
94 21:15:00 v255n.5cm-icrf
The basic method and frequencies for this experiment are the same as for the earlier v255 experiments (Oct, Jul, Mar 10 and earlier). The frequency setup for this session is identical to Oct2010. As for October the setup for the ICRF observations is to be 2 IFs with different polarizations, rather than 2 IFs with a single polarization which was used prior to September 09 (this avoids recabling at Hobart/Ceduna and significantly simplifies the setup changes). The times for the setup changes are given above.
The purpose of these observations is to obtain the first epoch for proper motion/parallax for Mon R2 and the third epoch for proper motion/parallax observations of the methanol maser sources G329.031-0.198, G329.029-0.205 and G329.066-0.308.
The Mon R2 observations run from 5 - 12:15 UT and should show a modest peak at a sky frequency of 6667.3 MHz. The G329.03-0.20 run from 13:00 - 21:15 UT and should show a modest peak at a sky frequency of around 6669.9 MHz during these observations.
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.
The 4 x 16 MHz bandpass setup requires feeding two separate LOs into IFP#1 and #2 on the DAS/frequency translator. Unlike the sessions prior to September 09, we wont need to recable during the run though. For Hobart the LOs should be set to 468 MHz (IFP#1) and 810 MHz (IFP#2) for the 4 x 16 MHz setup and 810 MHz for the 2 x 16 MHz setup. For Ceduna, if you set the agilent to 11.1 GHz rather than 11.4 GHz, then you can use the same LOs as at Hobart.
The level into IF#1 will change significantly between the two setups. Set the level into the DAS so that it is within range for both setups. Setup the system temperature measurement so that it works for both IFs for the v255n.5cm setup - it doesn't matter if the system temperature measurement doesn't work for the first IF during the ICRF observations as these are only to calibrate the delay. Please don't change the attenuation into the DAS when the setup changes as that may change the delay.
For the ATCA phase-up all available antennas CA01 through CA05 for this experiment. G329.031 and G329.029 are separated by about 30 arcseconds and the observation of G329.03-0.2 is at the mid-point of these two masers.
Setup as for a 2p-4IF experiment (dual DAS with huygens cable for entire experiment) with DAS1 tuned to the lower frequency and DAS2 to the upper frequency. Use the new features in cdisko version 4 to automate the changes of channel selection as per the following table.
0500 - 0545 and 0900 - 1102 : Only one of the two target sources (Mon R2) above the horizon at Parkes (G188.95 has set), Parkes will miss about 50% of scans during these times.
1102 - 1241 : All target sources below horizon at Parkes.
Observing times for Hart :
0833 - 0850 : ICRF observations
1029 - 1300 : Observations of MonR2/G188.95 and ICRF sources. After 13 UT there is no mutual visibility of any target sources until after 15 UT.
Observing times for Sheshan :
0830 - 1300 : Observations of MonR2/G188.95 and ICRF sources using same frequency setup for all observations (unlike other antennas). ICRF delay calibration observations are 08:15 - 09:00 UT and 12:15 - 13:00 UT