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askap-vast / vast-pipeline

This repository holds the code of the Radio Transient detection pipeline for the VAST project.
https://vast-survey.org/vast-pipeline/
MIT License
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Incorrect association? #711

Open ddobie opened 4 months ago

ddobie commented 4 months ago

https://dev.pipeline.vast-survey.org/sources/44717001/

This source has two measurements from a completely unrelated source included. The declination is roughly consistent, but the RA is off by >160 deg.

I have no idea what would cause this, especially since there's two other measurements of the same coordinates associated with a different (correct) source: https://dev.pipeline.vast-survey.org/sources/44332471/

ajstewart commented 4 months ago

This looks like the other way around, the association is good between those points, but somehow the forced fits has been done in the wrong location and attached to that source.

My guess is a bug in the ideal source coverage calculation, or a bug in the forced fits process that has got ID's crossed.

Edit: Suspicious that it's around RA 0, RA wrapping handling maybe?

ddobie commented 4 months ago

It seems to only occur for 3 sources out of the ~2M in the run: 43885418, 43891486,44717001.

All three are close to RA 0 for their detections, but all have forced fits measurements that are nowhere near where the detections are (74deg, 335deg and 164deg).