[vsnet-alert 3991] KZ Gem(?) in rare outburst

[Patrick Schmeer <extpasc@rz.uni-sb.de>]

My alert message:

KZ Gem appears to be in outburst at mag 14. Can you confirm?

 
Rod Stubbings' reply:

> Cannot confirm outburst.  I've had this field under observation and didn't
> notice any change tonight.  After your message I went out to look at the
> field again but could not see an outburst.  I'm using the vsnet chart.  The
> last few nights I thought there might have been an outburst but to me the
> close star above KZ Gem seems to have brightened a little.


My reply: 

There are three USNO-A2.0 stars very close to the catalogued position of
KZ Gem:
A) 06:53:02.496  +16:40:05.96  14.3  15.3
B) 06:53:02.468  +16:40:00.05  14.9  16.5
C) 06:53:02.744  +16:39:50.61  17.6  17.9
 
The star marked in DWS97 is just north of star C and southeast of B. 
Star B (or a very close companion of it) is the outbursting object. It
brightened by 2 magnitudes since Jan. 7.302 UT and was as bright as
star A (mag 14.3) on an unfiltered CCD image taken on Jan. 9.292 UT. 
I haven't yet received the original finding chart, but I would consider
it as highly unlikely that there are two outbursting objects so close
together (both reaching mag 14). It's much more likely that the wrong
star is marked in DWS97.

According to the GCVS KZ Gem is a dwarf nova with a photographic
magnitude range of 14.7-[18.5 and a mean cycle length of 258 days.
 
Astrometry, spectroscopy, and high-speed photometry during the current
rare outburst are very urgently required.
 
Patrick 
 
P.S.:
Please forget about CW Mon and turn your attention to this star (if 
still bright) - or RX J0640-24.

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