[vsnet-alert 11167] Possible dwarf nova: ASAS 150946-2147.7

[Grzegorz Pojmanski]

Possible dwarf nova: ASAS 150946-2147.7

Grzegorz Pojmanski, Dorota Szczygiel and Bogumil Pilecki of Warsaw 
University Astronomical Observatory report:
ASAS3V instrument of The All Sky Automated Survey (telephoto lens 200/2.8, 
diameter 70mm + CCD + Johnsons V  filter, 3 minute exposures, pixel size 
14.8 arcsec, rms astrometric accuracy - 4  arcsec) 

has detected possible outburst of an object located at
at RA = 15h 09m 46s  DEC = -21 47.7

This is the second outburst detected by ASAS at this position; the
previus one was detected on 23/07/2003 and lasted over 30 days.

This ASAS position coincides with two 2MASS sources: 
15094657-2147462 J=10.536 H=10.357 K=10.294
15094589-2147446 J=14.890 H=14.508 K=14.544
We suspected the fainter component of the blend being in outburst.

Average brightness of the blend outside outburst is V=11.5, and shows
a weak (0.1 mag) modulation with period P=0.351213 or 0.206187.

There is X-source present in the ROSAT PSPCC Survey image at this position.

 
Observations (current outburst):
    DATE      UT                       HJD      V
28/03/2009 06:07:10 (Mar 28.255) 2454918.7597 11.550 
28/03/2009 06:31:28 (Mar 28.272) 2454918.7760 11.482 
31/03/2009 05:57:54 (Mar 31.249) 2454921.7534 10.931 
31/03/2009 06:16:45 (Mar 31.262) 2454921.7660 10.951 
05/04/2009 08:51:07 (Apr 05.369) 2454926.8736 10.378 

Observations (previous outburst):
    DATE      UT                       HJD      V
14/07/2003 01:21:41 (Jul 14.058) 2452834.5605 11.495 
15/07/2003 03:42:01 (Jul 15.155) 2452835.6579 11.488
23/07/2003 01:41:09 (Jul 23.071) 2452843.5732 11.197
25/07/2003 04:29:58 (Jul 25.189) 2452845.6909 10.863
02/08/2003 00:47:11 (Aug 02.034) 2452853.5348 10.466
07/08/2003 01:38:26 (Aug 07.069) 2452858.5699 10.601
11/08/2003 00:56:32 (Aug 11.040) 2452862.5404 10.808
21/08/2003 01:08:22 (Aug 21.049) 2452872.5477 11.204
25/08/2003 00:03:22 (Aug 25.003) 2452876.5022 11.349
27/08/2003 00:05:06 (Aug 27.005) 2452878.5032 11.449
03/09/2003 23:47:21 (Sep 03.992) 2452886.4901 11.471

Light curve and images can be found on
http://www.astrouw.edu.pl/cgi-asas/asas_disc/150946-2147.7,4900,5000

Regards, Grzegorz Pojmanski