[vsnet-alert 14843] Re: CSS J221822.9+344511

[Denis Denisenko]

On Sun, Aug 12, 2012 at 11:02 AM, Taichi Kato
<tkato at kusastro.kyoto-u.ac.jp> wrote:

>    This CRTS OT (=CSS120812:221823+344509) apparently
> has an X-ray counterpart.
>
> 221823.7 +344506 (2000.0) 1RXS-F_J221823.7+344507 0.022 1.00 0.49

This object has also quite a bright ultraviolet counterpart GALEX
J221822.8+344508 with magnitudes FUV=18.12, NUV=18.04.

ROSAT hardness ratio HR1=1.00 is more typical for dwarf novae rather
than for polars.

There are 18 images from 8 different nights in Palomar/NEAT data
available from SkyMorph site. Amplitude of variability is quite small
- only 2 magnitudes (similar to CRTS archival lightcurve). Using
USNO-A2.0 1200-19082616 (22 18 28.14 +34 44 48.3) as a reference star
with R=14.9, I got the following magnitudes from 16 images suitable
for photometry:

  19980720.581  18.21
  19980720.602  17.99
  19980720.624  18.43
  20010614.418  17.88
  20010614.428  17.90
  20010614.440  17.74
  20010623.369  16.72
  20010623.380  16.72
  20010623.393  16.76
  20010812.336  18.18
  20020728.484  16.52
  20020728.495  16.46
  20020729.466  16.97
  20020926.122  16.61
  20020926.142  16.54
  20020926.163  16.70

The star was at the very edge of field of view on two more images of
2001-07-25 and 2001-08-12, but in both cases it was in the low state.

Note the outburst on 2001 June 23 with the star fainter 9 days before
(June 14) and 50 days later (Aug. 12). Outbursts seem to be quite
frequent. Maybe this is a new UGZ-type (Z Cam) variable?

Denis Denisenko