Likely counterpart for 2E 1050.8-6200
ATel #15646; Ignacio Negueruela
on 7 Oct 2022; 06:26 UT
Credential Certification: Ignacio Negueruela (ignacio@dfists.ua.es)
Subjects: Infra-Red, Optical, X-ray, A Comment, Star, Transient
The Swift/XRT error circle for 2E 1050.8-6200 (ATel# 15630) contains a moderately bright optical/near-IR source (Gaia DR3 25241943920520376704 / MASS J10524328-6215571), located about 3" East from the nominal position. The 2MASS magnitudes (J = 12.39, H = 11.88, Ks = 11.48) result in an infrared reddening-free index Q = -0.17, typical of stars with infrared excess. The Gaia XP pseudospectrum, though noisy, suggests strong H-alpha emission.
Gaia data (plx = 0.10 +/- 0.02 mas, BP-RP = 1.57) indicate low extinction in spite of a very high distance. The Bailer-Jones et al. (2021) photogeometric distance, which is unlikely to be accurate given the prior used, is 7.1 +/- 1.1 kpc. The observed magnitudes are compatible with a bright (i.e. early-type) Be star at that distance.
With BP = 15.26, this object is perfectly accessible for classification spectroscopy with a moderate-size telescope.
