Optical photometry of B2 2308+34 and MASTER OT J234843.23+250250.4
ATel #5564; E. Ovcharov (SU, Bulgaria), A. Kurtenkov (IA BAS, Bulgaria), P. Enikova (IA BAS, Bulgaria), G. Ganchev (SU, Bulgaria), V. Bozhilov (SU, Bulgaria), Ts. Tsvetkov (SU, Bulgaria), Ts. Genkova (SU, Bulgaria)
on 9 Nov 2013; 12:12 UT
Credential Certification: Evgeni Ovcharov (evgeni@phys.uni-sofia.bg)
Subjects: Optical, Cataclysmic Variable, Quasar
We report optical photometry of the quasar B2 2308+34 (ATel # 5517, ATel # 5477, ATel # 5487) and of the new bright cataclysmic variable MASTER OT J234843.23+250250.4 (ATel # 5526). The brightness of both objects is decreasing with a few tenths of magnitude for four days. The observations are carried out with the 0.35m Newton telescope + CCD STL11000M at the SAO Plana (ATel # 5558).
The magnitudes given are obtained from a photometric solution using magnitudes of The USNO-B Catalog (Monet et al. 2003, AJ, 125, 984) and UCAC4 Catalogue (Zacharias et al. 2013, AJ, 145, 44):
B2 2308+34
2013 10 29.83194 UT, V=16.68+/-0.03
2013 10 29.81579 UT, R=16.19+/-0.03
2013 10 29.82240 UT, I=15.20+/-0.04
2013 11 02.84440 UT, V=17.38+/-0.08
2013 11 02.83782 UT, R=16.70+/-0.06
2013 11 02.84111 UT, I=15.89+/-0.10
MASTER OT J234843.23+250250.4
2013 10 29.84551 UT, B=15.53+/-0.02
2013 10 29.85009 UT, V=15.44+/-0.02
2013 10 29.85486 UT, R=15.10+/-0.02
2013 11 02.85764 UT, B=16.12+/-0.02
2013 11 02.86091 UT, V=15.94+/-0.03
2013 11 02.85109 UT, R=15.45+/-0.03
2013 11 02.85486 UT, I=15.44+/-0.11
