Possible orbital period of eRASSt J100130.9-614021
ATel #13845; P. Mroz (Caltech), A. Udalski (Warsaw U.), on behalf of the OGLE team
on 1 Jul 2020; 15:06 UT
Credential Certification: Przemek Mroz (pmroz@astrouw.edu.pl)
Subjects: Optical, X-ray, Transient
A new X-ray source eRASSt J100130.9-614021 (ATel #13844) is located in the field GD2060 that has been regularly observed since 2017 by the OGLE survey as part of the OGLE Galaxy Variability Survey (Udalski et al. 2015, Acta Astron. 65, 1).
The position of eRASSt J100130.9-614021 is coincident with a bright source (I=13.38) listed as GD2060.13.17175 in the OGLE database, located 0.66 arcsec away from the X-ray source, within its error circle.
The OGLE light curve reveals a low-amplitude (~0.06 mag peak-to-peak), sinusoidal variability with a period of 1.122474 +/- 0.000055 d, which may be a rotation period of the source. Alternatively, the periodicity may be due to ellipsoidal modulation, in which case the orbital period of the binary system is two times longer (~2.24494 d).
