ResultsPage
This page contains some images/links to images produced during the workshop. If you think something interesting is missing, please feel free to add your own. You can either upload attachments directly to the wiki, or place the images under ~/public_html in your home directory on lofar9 (which is visible on the web as http://lofar9.astron.nl/~yourname/)
We took the following calibration steps:
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Solved for the (apparent) fluxes of 3C343 and 3C343.1. This produces a very rough fit, since the phases are still unaligned.
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Solved for G phases; went back and redid the flux solution -- this now gives almost precise fluxes since the phases are almost in alignment -- then solved for G phases again, and did some flagging. This is the residual image.
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Solved for G amplitudes. See residual image. Note how the artefacts left behind by the off-center source clearly suggest off-center gain errors.
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Went back and ran another flux solution, which didn't produce any visible improvement.
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Added an E-Jones to the off-center source, to account for differential gains/phases. Did a simultaneous solution for G/E phases, but things didn't improve much. The inspectors did show significant off-center phase differences though.
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Solved for G/E amplitudes, and that really got rid of the off-center source!
After the workshop, at Jan's instigation, I made an LSM for the background sources in the field, using NVSS. I then ran a few more solutions, eventually solving for the 60 brightest background sources and realigning the phases once more. The best residuals are here. Some background sources fail to subtract cleanly: I see what I think is an extended source, a few positional errors, and also a single LSM source where we actually have a double source.