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Description Measuring the proper motions of the Large and Small Magellanic Clouds
Antennas At-Cd-Ho-Mp-Pa
Start 329 07:00:00
Stop 329 21:00:00
PI S.P. Ellingsen

Setup v490b.1cm-icrf:

Station Modes At Cd Ho Mp Pa
Channel 1 IFP#1-LO 22000 - 22016 MHz USB RCP
Channel 2 IFP#1-HI 22016 - 22032 MHz USB RCP
Channel 3 IFP#2-LO 22500 - 22516 MHz USB LCP
Channel 4 IFP#2-HI 22516 - 22532 MHz USB LCP
DAS 1 Skyfreq 22016 & 22516 MHz
Bandwidth 16 MHz
DAS Mode (telescope)

Setup v490b.1cm:

Station Modes At Cd Ho Mp Pa
Channel 1 IFP#1-LO 22211 - 22227 MHz USB RCP
Channel 2 IFP#1-HI 22227 - 22243 MHz USB RCP
Channel 3 IFP#2-LO 22211 - 22227 MHz USB LCP
Channel 4 IFP#2-HI 22227 - 22243 MHz USB LCP
DAS 1 Skyfreq 22227 MHz
Bandwidth 16 MHz
DAS Mode (telescope)

Mode changes:
329 07:00:00 v490b.1cm
329 08:05:00 v490b.1cm-icrf
329 09:00:00 v490b.1cm
329 14:00:00 v490b.1cm-icrf
329 14:45:00 v490b.1cm
329 20:18:00 v490b.1cm-icrf


Due to popular demand V490 has copied the basic strategy used for the V255 series of methanol maser astrometry experiments. There are two different frequency setups, the “ICRF” observations to calibrate the tropospheric delay has 2 IFs with different polarizations. The second setup (the one used for the majority of the time) has a single IF with dual polarisation. The times for the setup (mode) changes are given above.

The purpose of these observations is to obtain the second epoch for proper motion observations of water masers in the SMC and LMC.

Observing comments for each antenna:

Hobart, Ceduna :

The 4 x 16 MHz bandpass setup requires feeding two separate LOs into IFP#1 and #2 on the DAS/frequency translator. For both Hobart and Ceduna the LOs should be set to 706 MHz (IFP#1) and 206 MHz (IFP#2) for the 4 x 16 MHz setup and 495 MHz for the 2 x 16 MHz setup. For Hobart use 16.37 GHz as the Agilent frequency and for Ceduna use 17.47 GHz. For the 4×16 MHz setup 880.2 and 900.2 MHz should give coherence in IF#1 and IF#2 respectively, while for the 2×16 MHz use 888.64 MHz to check coherence (these tones apply for both Hobart and Ceduna).

The level into IF#2 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 v490b.1cm setup - it doesn't matter if the system temperature measurement doesn't work for the second 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.

Parkes, ATCA, Mopra :

For the ATCA please phase-up antennas CA01 through CA04 for this experiment. The source 0100-760, 0601-706 and 0530-727 should all be suitable for phasing the array (in addition to the fringe finder sources) and have been marked with the AUTOPHASE_DETERMINE intent in the vex file.

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. Record using the following channel ranges.

v490b.1cm Channels 5-8
v490b.1cm-icrf Channels 1,2,7,8

cdisko should make these changes automatically but it should be monitored carefully.

Parkes LO can be controlled using the “losched” command. It assume the initial setup has been made usign a normal lo_setup file. Run if as pksobs on joffrey:

> losched v490b.losetup

v490b.1cm frequencies at Parkes can be setup using the 2013Nov_13MMd.cmd and v490b.1cm-icrf using 2013Nov_13MMe.cmd

Observing comments for each antenna:

Observing Logs


Monica log information - EXPERIMENTAL:

lbaops/lbanov2013/v490b.txt · Last modified: 2015/12/18 16:38 (external edit)