[vsnet-alert 15240] Re: OT J122221.6-311525 = bright CRTS transient

[Hiroyuki Maehara]

 The object was detected at Vmag=11.8 by the Kyoto/Kiso Wide-field Survey
on Dec 26.

OT_J122221.6-311525 20120328.63044 <11.0V KW2 --
OT_J122221.6-311525 20120328.63083 <11.0V KW2 --
OT_J122221.6-311525 20120331.61500 <10.9V KW2 --
OT_J122221.6-311525 20120331.61535 <10.7V KW2 --
OT_J122221.6-311525 20120407.58847 <10.7V KW2 --
OT_J122221.6-311525 20120407.58882 <10.8V KW2 --
OT_J122221.6-311525 20120414.57725 <11.2V KW2 --
OT_J122221.6-311525 20120414.57762 <11.3V KW2 --
OT_J122221.6-311525 20120417.58544 <9.1V KW2 --
OT_J122221.6-311525 20120417.58581 <9.5V KW2 --
OT_J122221.6-311525 20120427.55866 <11.2V KW2 --
OT_J122221.6-311525 20120427.55903 <11.0V KW2 --
OT_J122221.6-311525 20120428.56146 <10.4V KW2 --
OT_J122221.6-311525 20120428.56181 <10.9V KW2 --
OT_J122221.6-311525 20120512.52359 <11.1V KW2 --
OT_J122221.6-311525 20120512.52396 <10.9V KW2 --
OT_J122221.6-311525 20121226.87655 11.844V KW2 0.245
OT_J122221.6-311525 20121226.87690 11.806V KW2 0.246
OT_J122221.6-311525 20121226.87741 12.020V KW2 0.273

KW2: Kyoto/Kiso Wide-field Survey
     f=105mm lens (F/2.0) + SBIG ST-8XME



On Fri, Jan 04, 2013 at 10:11:35, Taichi Kato wrote:
> OT J122221.6-311525 = bright CRTS transient
> 
> SSS130101:122222-311525 http://nesssi.cacr.caltech.edu/SSS/20130101/1301010310804113661.html 12 22 21.63 -31 15 24.9 12.36 No SDSS object CV
> 
>    No outburst was recorded in ASAS-3.
> 
> ROSAT source:
> 122221.4 -311544 (2000.0) 1RXS-F_J122221.5-311545 0.050 0.75 0.05
> 
> ===
> 
> ATEL #4699							     ATEL #4699
> 
> Title:	Detection of a Bright Optical Transient by CRTS
> Author:	A. J. Drake, S. G. Djorgovski, A. A. Mahabal, M. J. Graham,
> 		R. Williams (Caltech); R. McNaught (ANU); J. Prieto (Princeton); M.
> 		Catelan (PUC Chile); E. Christensen, S. M. Larson (LPL/UA).
> Queries:	ajd at cacr.caltech.edu
> Posted:	4 Jan 2013; 00:24 UT
> Subjects:Optical, Cataclysmic Variable, Transient, Variables
> 
> Further to ATel#4678, here we report the CRTS discovery of 
> <a href=http://nesssi.cacr.caltech.edu/SSS/20130101/1301010310804113661.html>SSS130101:122222-311525</a>.
> 
> This source was detected at V = 12.3+/-0.1 in four images taken by the
> <a href=http://www.mso.anu.edu.au/~rmn/>Siding Spring Survey</a>  
> on 2013-01-01 UT and is located at RA=12:22:21.63 Dec=-31:15:24.9 
> 
> Based on 230 measurements (from 90 nights of observation between Aug. 2005
> and Aug. 2012), the  
> object has an average magnitude of V ~19. The source exhibits variability
> at the  
> level of ~1 magnitude in this archival data, yet shows no prior outbursts.
> 
> The source is well detected by GALEX (with NUV =18.9+/-0.1 and FUV 19.6+/-0.2)
> 
> and may match ROSAT X-ray source 1RXS J122221.5-311545. 
> The object is also a very good positional match to radio source NVSS J122222-311529.
> 
> However, it is no clear source is seen in radio observations from the SUMSS
> and VLSS 
> surveys. 
> 
> This large, bright outburst, along with the UV detection and correspondence
> with an X-ray  
> source, are most consistent with a cataclysmic variable. However, association
> with  
> a radio source is generally unexpected for CVs and may be coincidental
> or spurious. 
> Further observations are required to determine the nature of this event.
> 
> A finding chart is available  
> <a href="http://crts.caltech.edu/ATEL/SSS/1301010310804113661.atel.html">here</a>.
> 
>