Hi,
I am currently analysing nuclear transients observed by LSST using Lasair. To filter out objects of interest, I have been using ‘separationArcsec’ from the Sherlock table. I have noticed however that a large amount of objects are associated with an incorrect host (of about 16000 objects in my sample, ~1000 have a separation larger than 10"). For some, e.g. 314011776613613633 and 314046941676175420, their host galaxy are incredibly faint and/or the detections are likely not real. For others, e.g. 170019716316790837 , 314011776166920286 and 170019716290052199, clearly the wrong host is assigned. Once you look up the coordinates of the actual host in NED, the correct galaxy is found. Here are images of the mentioned examples:
I wonder now why this is? I assume it is because the catalogs available to Lasair are not as up to date as those in NED. I could not find it, but is there a list of galaxy catalogs that are currently being used by Lasair? The one in the documentation does not seem up to date. Is there also a plan to add more catalogs like WISE in the future and could you give me an estimation of when this would be?
An additional question: I would like to use the ‘major_axis_arcsec’ parameter in the Sherlock table, but this is NULL for all objects I have looked at so far. Is there a plan of implementing this in the future?
Thank you very much!
Kindly,
Erin