Classification of ComCam Stars

I’m looking for surveys coincident with the six ComCam fields, where the types of stars are identified and below Rubin saturation magnitudes. Gaia has stars broken down by subclasses and covers the regions but very few stars are dim enough (> 17? 18?) to use with ComCam data. SDSS specobj tables also contain subclasses but they’re too far north. I haven’t found anything for PanStarrs or ZTF yet. I’m hoping to use known stars’ colors to train ComCam data.

Hi Bob – The ECDFS and EDFS fields are definitely within the Dark Energy Survey (DES) footprint, so will have colors in bands similar to the Rubin bandpasses. Rubin_SV_38_7 is in the DECALS (DECam Legacy Survey) footprint, so should also have good-quality DECam data. If you need stellar spectroscopic classification, I’m not sure what’s available, but at least the DECam datasets should get you started on photometry. And Gaia, as you mentioned – there should be a decent number of stars overlapping Gaia.

Hope this is helpful!

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Thank you Jeff, I am seeing some success with Gaia, but most magnitudes are too bright to compare with DP1 observations. Do you know low in magnitude DP1 stars can be before they’re untenable? Also, I’ll look for DECam-derived stellar classes.

Looks like DECam is my best bet:

There are certainly stars fainter than G=14 in the DP1 fields. Are the stars in this plot so bright because you are restricting to only stars with spectra?

The TIMEDOMES in-kind contribution that I lead is releasing VST images of the LSST DDFs taken in the past 15 years. Would these be useful? We cover COSMOS, CDFS, ELAIS-S1, XMM-LSS.

I think you’re right, Jeff, I may be restricted by the need for Gaia spectra to classify the stars. I started with 610,000+ objects. The maximum magnitudes were 17.6 (G band( and 21.3 (BP band). Of the six ComCam fields, the catalog only had objects in the Rubin 38 7 field (51) and the Rubin 95 -25 field (6), with maximum magnitudes of 15.2 (G band) and 16.4 (BP band). I’ll go back and look at DESI catalogs again and check out TIMEDOMES as suggested by Maurizio (thank you Maurizio!). I may need to figure out another way to compare objects. Maybe transients or galaxies. Maybe compare ComCam field colors to DECam and PanStarrs.

Thanks Marizio! Are there object catalogs as well?