H-alpha observations of M31 nova candidates AT2022alr and AT2022uz
ATel #15198; A. Valcheva (Sofia University, Bulgaria), M. Minev (Sofia University; IA with NAO, BAS, Bulgaria), I. Dimitrova (Sofia University; IA with NAO, BAS, Bulgaria), E. Ovcharov (Sofia Univeristy, Bulgaria), P. Nedialkov (Sofia University, Bulgaria)
on 3 Feb 2022; 20:40 UT
Credential Certification: Antoniya Valcheva (valcheva@phys.uni-sofia.bg)
Subjects: Optical, Nova, Transient
We report H-alpha photometry of two recent nova candidates in M31 - AT 2022alr (= PNV J00424699+4115532) and AT 2022uz (= XM63MZ)(= PNV J00430928+4116013). The observations in narrowband H-alpha (FWHM of 30Å) were performed with the FoReRo2 focal reducer at the 2m RCC telescope at the NAO Rozhen, Bulgaria on 2022 Jan 31.712 UT under nonphotometric weather conditions (FWHM ~ 3 arcsec). Photometric magnitudes were obtained from 5x300 sec co-added frames (H-alpha image can be found here). Additional B-magnitudes are also available.
AT 2022alr was discovered by Jiangao Ruan, Mi Zhang and Xing Gao (Xingming Obs) on 2022 Jan 25.556 UT very close at 30.1" east and 15.3" south of the center of M31. Our observations show that the transient is very bright in H-alpha with a magnitude of 14.89±0.03 and this confirms the object classification as a nova. B-magnitude of the nova is 17.27±0.03 mag (5x300 sec; 2022 Jan 31.712 UT).
We have also detected the transient AT 2022uz discovered on 2022 Jan 16.587 UT by M. Zhang and X. Gao. Independent discovery was reported by Hornoch et al. (ATel #15170) who designated the slowly brightening transient as M31N 2022-01a. AT 2022uz is visible in H-alpha and have a magnitude of 17.66 ±0.08 mag. Obtained B-magnitude is 18.46 ±0.02 mag (5x300 sec; 2022 Jan 31.712 UT).
This work was partially supported by the Ministry of Education and Science of the Republic of Bulgaria, National RI Roadmap Project D01-383/18.12.2020 and NSF Bulgaria grant DN18/10-11.12.2017.
