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: http://www.atnf.csiro.au/vlbi/wiki/index.php?n=LBASep2009.V255F
Дата изменения: Unknown Дата индексирования: Tue Apr 12 14:56:04 2016 Кодировка: Поисковые слова: п п п п п п п п п п п п п п п п п п п |
V255Fv255f
Setup v255f.5cm:
Setup v255f.5cm-icrf:
Mode changes: Comments:At Cd Ho Mp Pa: Single pol dual frequency setup required. Will need special DAS setup Background:The basic method and frequencies for this experiment are the same as for the v255 experiments in Feb 09 (and earlier). The frequency setup for this session is identical to February, the only difference is that the setup for the ICRF observations is to be 2 IFs with different polarizations, rather than 2 IFs with a single polarization as previously (this avoids recabling at Hobart/Ceduna and significantly simplifies the setup changes). Unlike for previous epochs we will change the setup for the ICRF observations in the middle of the run, as well as for the beginning and end. The times for the setup changes are given above. The purpose of these observations is to obtain the fourth epoch for proper motion/parallax observations of the methanol maser sources G9.62+0.20 and G8.68-0.37. Previous epochs were v255a (Mar08), v255b (Aug08) and v255f (Feb09). We will observe both masers and phase calibrators with dual polarization 2x16 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 6668.2 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. 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. Hobart, Ceduna :The 4 x 16 MHz bandpass setup requires feeding two separate LOs into IFP#1 and #2 on the DAS/frequency translator. Unlike previous epochs 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. Parkes, ATCA, Mopra :NOTE: the setup for the 4 x 16 MHz (ICRF sessions) differs from previous epochs, we now record dual polarization for both the ICRF and maser setup. This may require stopping the recorder and changing modes in cdisko? Observing comments for each antenna:
Observing LogsParkes onsource flagging |