[vsnet-alert 14788] Re: OT J170609.7+143452 outburst

[Seiichi Yoshida]

Dear Denis Denisenko,

Thank you very much for your report on OT J170609.7+143452.

I published our image of this dwarf nova at:

  http://www.aerith.net/misao/report/variable/OT_J170609.7+143452.jpg

I wrote it was 14-15 mag. But maybe it was overestimated. It can be
around 15 mag actually. It was near the limit of our detection. But it
was clearly visible on our three images.

Best regards,

> Dear all,
> 
> MASTER-Tunka has accidentally observed this field less than 2 hours
> ago with 180-sec exposure starting on 2012-07-19 at 14:53:08 UT. The
> unfiltered magnitude of CRTS OT J170609.7+143452 is 16.6+/-0.1. This
> is well above the quiescent magnitude of this variable (typically
> 17.7-18.4 with the same USNO-B1.0 Red zeropoint), but well below the
> outburst magnitude reported from 2 days old MISAO observation. It
> seems the star is already fading after the outburst now.
> 
> I have also checked the MASTER-Kislovodsk database, and curiously
> enough the discovery outburst of CSS 090205:170610+143452 was observed
> by MASTER on 2009-01-24 on three images at 03:29:14, 03:30:50 and
> 03:32:21 UT at 14.3, 14.4 and 14.7 magnitudes, respectively. But the
> automatic transient detection by MASTERs had not started yet at that
> time.
> 
> The variable was at quiescence on 2012 June 11 MASTER-Kislovodsk
> images, as well as on June 08 and June 17 CSS images.
> 
> Denis in Moscow
> 
> On Thu, Jul 19, 2012 at 7:49 PM, Seiichi Yoshida <comet at aerith.net> wrote:
> > Dear colleagues,
> >
> > We detected that a dwarf nova OT J170609.7+143452 is bright at around
> > 14-15 mag at July 17.55(UT) from Nobuo Ohkura's survey images with
> > 350-mm camera lens + f/2.8 reducer lens + SBIG STL-1001E in the course
> > of the MISAO Project. It was not visible on the images on May 23 and
> > June 13.

--
Seiichi Yoshida
comet at aerith.net
http://www.aerith.net/