March 3, 2011 Tiger Team
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IP: 184.108.40.206 (NRAO CV-RM209)
Toll-free: 866 560 2652
Toll: 517 308 7468
Attendees: Crystal, Ed, Scott, Nuria, Mark, Todd, Al, Kartik, Richard, Eric
- SV data
- 23-point mosaic of a point source was successfully observed with SB and reduced in casa. Image accurate to 4%. A more accurate result was obtained when the assumed primary beam in casa was broadened by 10%.
- Form of beam data in CASA? Grid of sensitivities for PB?
- Continuing discussions with Lindsey about pipeline: about 'phantom' spectral line in BetaPic, more scientific input to John Lightfoot, and subtraction of continuum from line (simulated data may be used).
- George M returned from a successful polarization campaign at the OSF. 1) casa linear polarization software is working; 2) D-terms average about 1.5%; 3) However, there are significant D-term variations with frequency (main variation has a period about 2 GHz, and with distance from the beam center that may affect polarization images at the 1% level. Richard and Robert and others are trying to determine the cause of the variations which may be caused by reflections associated with the subreflecter and other antenna structures. Observations at band 6 and higher are being made as the weather improves.
- Offer continuum observations only is Richard's recommendation with strong caveats
- ASAC - anything relevant for this group?
- CSV-624 (Early science 16 antennas)
- Compact: Has anyone investigated Richards mod to 3b?
- Med: Progress?
- Ext (750max baseline):
- Here is the presentation that REH made to the ASAC: Cycle_0_Configurations.pdf
- The general feeling coming out of this is that three configurations is too many for Cycle 0. Given especially that the high resolution work cannot be done until after the shut-down, the preference of many people was to wait until Cycle 1 for that. It is also true that starting in one configuration on 30th Sept and then shifting to another one in late November does not make people comfortable.
- We hope to decide what to do on Friday. If it is decided that we only specify two arrays in the call, then obviously we still have to choose which two. As things stand we have four on offer:
- Small FWHM 105m (Compact 3 - with or without modifications)
- Medium FWHM 280m
- More comfortable, less of a risk in terms of understanding performance / calibration etc.
- Matches Band 3 and 6
- Extended FWHM 420m (This size was in the first set studied by Frederic. Eric and I both thought that case 7 looks pretty good
- Will be able to test with at least some longer baselines
- Gives matching band 3 and 7 or 6 and 9
- Combining configs shouldn't be included
- Large FWHM 750m
- Matching between bands 3 to 9
- I think it is important to consider the overlap in UV coverage between these arrays as well as the maximum resolution.