Outburst of Cataclysmic Variable 1RXS J231935.0+364705
ATel #2282; D. V. Denisenko (IKI, Moscow)
on 5 Nov 2009; 14:53 UT
Distributed as an Instant Email Notice Request For Observations
Credential Certification: S.A.Grebenev (sergei@hea.iki.rssi.ru)
Subjects: Optical, X-ray, Request for Observations, Cataclysmic Variable
We report the first real-time detection of the outburst (from 19.0 mag to 14.5 mag on Nov. 5, 2009) of an optical counterpart of the poorly studied ROSAT X-ray source 1RXS J231935.0+364705 in Andromeda. Earlier (in 2007) we identified it with the NSVS variable object 9022680 (see http://hea.iki.rssi.ru/~denis/NSVS9022680.gif ). NSVS 9022680 showed a dwarf nova-like outburst in November 1999. Due to the poor angular resolution of ROTSE-I (14") this object is actually a blend of two stars separated by 18.5". The fainter (north-western) star is showing outbursts. The name and coordinates of the new cataclysmic variable are: USNO-B1.0 1267-0564384 RA=23h19m36.06s, +36o47'00.3" (J2000.0).
The color-combined (BRIR) 10'x9' DSS finder chart of RX J2319.6+3647 is available at http://hea.iki.rssi.ru/~denis/J2319+3647-comps.gif (position of the variable object is marked with dashes). Another outburst was recorded on the POSS-II infrared plate taken on 1995 Aug. 28. This is why the variable has peculiar colors in USNO-B1.0 catalogue (B1-R1=0.0, R1-R2=0.0, R2-I=4.0): B1=17.73 R1=17.73 B2=18.66 R2=17.73 I=13.63.
The new variable was monitored with the Bradford Robotic Telescope since October 2009. The following photometry has been obtained:
Time (JD) YYYY-MM-DD.ddd R mag
----------------------------------
2455121.542 2009 10 17.042 18.74
2455127.552 2009 10 23.052 18.96
2455140.522 2009 11 05.022 14.48
The outburst amplitude (about 4.5 mag) and duration of the 1999 outburst in ROTSE data suggest that the new variable is a dwarf nova of the SU UMa (UGSU) subtype. Follow-up photometric observations are requested to determine the orbital period and to search for possible superhumps. Checking the archival survey data for previous outbursts is also encouraged.
1RXS J231935.0+364705 page
