Central Bureau for Astronomical Telegrams

CBAT "Transient Object Followup Reports"

TCP J16420534+8156125

TCP J16420534+8156125   2023 08 01.0103*  16 42 05.34 +81 56 12.5  12.9 U             UMi       9 3

2023 08 01.0103

The transient is visible in three images captured around 2023-08-01.0103 UT using the second wide-field camera of the NMW survey: 135mm f/2.0 telephoto lens + unfiltered SBIG STL-11000 CCD. The position of the transient is uncertain at ~10" level due to a large pixel scale of the camera, which is 13.8"/pix. Most likely, the transient is a dwarf nova outburst of the white dwarf candidate Gaia DR3 1710719047756794368 16:42:09.313 +81:55:55.86 J2000 (G = 20.5, Plx = 1.9 +/-0.6mas) listed by Gentile Fusillo et al. (2021, MNRAS, 508, 3877). The ASAS-SN forced photometry (Shappee et al. 2014, ApJ, 788, 48; Kochanek et al. 2017, PASP, 129, 104502) at the Gaia position confirms the outburst on 2023-08-01.1868 UT: https://asas-sn.osu.edu/sky-patrol/coordinate/2671df15-f050-400a-9e86-9f798c24110e The plate-solved FITS images obtained with the second NMW camera are available at http://scan.sai.msu.ru/~kirx/img/TCPJ16420534+8156125/ ---- Stanislav Korotkiy (Astroverty, Ka-Dar), Kirill Sokolovsky (UIUC, SAI MSU), Olga Smolyankina (Observatory of Omsk CPCT), Anna Prokudina, Sergei Ostapenko

2023 08 02.1866

Position end figures were 09.35 and 56.17 in R.A. and Dec., respectively. Gaia DR3 1710719047756794368 exist at this position. Photometry were V=13.19 and Ic=13.16 with T24 (0.61-m f/6.5 reflector + FLI-PL09000 CCD) iTelesciope.NET @ Sierra Remote Observatory at Auberry California USA. I use a red star as comparison, thus, photometric error might be large. https://meineko.com/ccd/TCP_J16420534+8156125.jpg -Seiichiro Kiyota (Kamagaya, Japan)