[vsnet-alert 15413] MASTER OT J062323.48+730744.0 (14.7m)

[Denis Denisenko]

Vsevolod Yecheistov has found yet another bright optical transient in
MASTER-Amur survey images - MASTER OT J062323.48+730744.0 (see ATel
#4821: Three OTs detected by MASTER,
<http://www.astronomerstelegram.org/?read=4821>).

The object has shown at least three previous outbursts in MASTER data:

MASTER OT J062323.48+730744.0
  20100828.906   187C   MASTER-Kislovodsk
  20100828.937   185C   MASTER-Kislovodsk
  20110119.728   174V   MASTER-Amur
  20111107.728  14.96C  MASTER-Kislovodsk
  20111107.763  14.98C  MASTER-Kislovodsk
  20120324.646  14.42V  MASTER-Amur
  20120324.678  14.58V  MASTER-Amur
  20120820.604   174C   MASTER-Amur
  20120820.636   178C   MASTER-Amur
  20120930.680  14.57C  MASTER-Amur
  20120930.711  14.48C  MASTER-Amur
  20121116.498   175C   MASTER-Amur
  20121212.531   181C   MASTER-Amur
  20130108.606  14.90C  MASTER-Amur
  20130116.640   183C   MASTER-Kislovodsk
  20130116.672   184C   MASTER-Kislovodsk
  20130214.686  14.67C  MASTER-Amur
  20130214.717  14.73C  MASTER-Amur

It appears to be a frequent outburster, so is likely a new UGZ or UGSU
dwarf nova.

Entries in various catalogues:
USNO-A2.0 1575-02539528 (06 23 23.49 +73 07 42.8 R=18.3 B=18.5)
USNO-B1.0 1631-0067280 (06 23 23.426 +73 07 43.05 B1=19.44 R1=18.51
B2=19.36 R2=17.48 I=15.30)
GSC 2.3.2 (06 23 23.525 +73 07 43.07 F=17.32 j=19.52 V=15.51 N=15.23)
GALEX J062323.5+730742 (FUV=20.30+/-0.16, NUV=18.56+/-0.04).
It was in outburst on 1995 Feb. 07 POSS-II infrared plate and on two
1983 Nov. 05 Quick-V plates, hence such curious colors. GALEX
far-minus-near UV color index of 1.74 is also quite peculiar for CVs.

Follow up observations are required. This variable in Camelopardalis
is circumpolar for most of northern hemisphere observers (and beyond
CRTS, SDSS and NEAT coverage). The discovery and reference images are
available at http://master.sai.msu.ru/static/OT/062323.48730744.0.png

Denis Denisenko
Member of MASTER team at SAI MSU