casangi / xradio

Xarray Radio Astronomy Data IO
https://xradio.readthedocs.io/en/latest/
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Suggestions and curiosities #298

Open arpan-52 opened 3 weeks ago

arpan-52 commented 3 weeks ago

Hi,

My feedback is based on the problems that I typically faced while handling MS V2 and then I do not want them 10 years down the line.

  1. Can the MS v4 also include primary beam tables which will be particularly useful when processing cross baselines with two different size antennas?
  2. Without storing it as an n-dimensional array, is it feasible to store it as a raw binary and then provide a header for the interferometric software to interpret it?
  3. Can we only store the gridded data instead of the whole picture and then run calibration, flagging everything in the uvw plane?
  4. I feel the uvw keyword is unnecessary as it can be calculated immediately. But I do not have any idea if it makes more sense to calculate it once, store it, and then read it again and again or calculate it every time when needed. I think the same goes for the weights, which can be calculated while gridding.
  5. I think the MS should include a section specifically for observatories to populate with timestamps, antennas, or stations that are unavailable or have known corruption issues throughout the observation. Based on this information, we could automatically delete portions of data known to be corrupted, saving significant storage space. This would also improve detection of faint and moderate RFI outliers, allowing faster and more efficient processing.

Lastly, I really appreciate the need for a new format that will not be a bottleneck in the processing and I would like to contribute from my side testing the MS V4 with uGMRT data.