[vsnet-alert 24500] Re: MASTER OT J194955.17+455349.6 outburst

Fri Jul 31 21:15:15 JST 2020

MASTER OT J194955.17+455349.6 = 1RXS J194954.8+455347 was discovered in
outburst to 16.4m on 2014 July 18.556, see
http://www.astronomerstelegram.org/?read=6325

Looking at the ZTF DR3 light curve (F. Masci et al., 2019), this variable
has three "quantum states": deep hibernation (or "sleep") at around 21m,
intermediate (or "wake up") at 19m and active with dwarf nova outbursts to
~16m: http://scan.sai.msu.ru/~denis/J194955+455349-ZTF-DR3-LC.gif

The transition from deep hibernation to intermediate state occured on 2018
July 21-23, see http://scan.sai.msu.ru/~denis/J194955+455349-ZTF-2018.gif

ZTF DR3 data for this object are ending on 2019 Dec. 20. The current ZTF
light curve is available at https://lasair.roe.ac.uk/object/ZTF18abjfmwd/
The current outburst appears to be the brightest one since the discovery.

Denis Denisenko

On Fri, Jul 31, 2020 at 2:27 AM Taichi Kato <tkato at kusastro.kyoto-u.ac.jp>
wrote:

> MASTER OT J194955.17+455349.6 outburst
>
>   YYYYMMDD(UT)   mag  observer
>   20200724.2809 18.631zg  (Zwicky Transient Facility Lasair (Masci+ 2019))
>   20200727.3864 18.914zg  (Zwicky Transient Facility Lasair (Masci+ 2019))
>   20200729.3043 17.254zg  (Zwicky Transient Facility Lasair (Masci+ 2019))
>   20200730.3041 15.419zg  (Zwicky Transient Facility Lasair (Masci+ 2019))
>