Independent Discovery of a Probable Nova in M31
ATel #14842; A. Valcheva (Sofia University, Bulgaria), A. Kostov (IA and NAO, BAS, Bulgaria), P. Nedialkov (Sofia University, Bulgaria)
on 10 Aug 2021; 09:54 UT
Credential Certification: Antoniya Valcheva (valcheva@phys.uni-sofia.bg)
Subjects: Optical, Nova, Transient
We report the independent discovery of a probable nova in M31 on 5x300 sec co-added R-band CCD images taken on 2021 Aug 8.951 UT with the 50/70 Schmidt telescope at Rozhen NAO Bulgaria. We were able to confirm the transient on 5x300 sec co-added R-band images taken on 2021 Aug 9.968 UT with the same instrumentation and we detected an increase in its brightness.
The object was first announced on Aug 9.033 UT by Conjat and designated as AT2021vgi. We found the object at a position RA(J2000)=00h42m39s.58 and DEC(J2000)=+41o09'03".5, which is 641.1" west and 2476.1" south of the center of M31 (see the discovery image here). The following R-magnitudes are obtained:
2021 Aug 6.988 UT, [20.4; 8.951, 19.1 ± 0.1; 9.968, 18.66 ± 0.08 mag.
Additional BV photometry of the object is also available:
2021 Aug 8.977, B=19.5 ± 0.1 mag
2021 Aug 8.966, V=19.4 ± 0.1 mag.
We found that the transient is located at a distance of 0.''45 from M31N 2009-11b (Shafter et al., 2011, ApJ, 734, 12).
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.
