[vsnet-alert 10132] Re: V2491 Cyg dramatic fading

[Luboš Brát]

Here is our BVRI light curve of V2491 Cygni. Last BVRI data (KOC = Radek 
Kocian, Ostrava observatory) shows significant decline. Data can be found 
under the light curve.

http://var2.astro.cz/meduza/light-curves-ccd.php?star=V%202491%20Cyg&shv=Cyg

With best regards
Lubos Brat
- Czech Variable Star Section


----- Original Message ----- 
From: "Taichi Kato" <tkato at kusastro.kyoto-u.ac.jp>
To: <variable_star_forum at yahoogroups.com>; 
<vsnet-alert at ooruri.kusastro.kyoto-u.ac.jp>; <vsnet-alert at yahoogroups.com>; 
<vsnet-campaign-nova at ooruri.kusastro.kyoto-u.ac.jp>
Sent: Tuesday, April 29, 2008 2:47 AM
Subject: [vsnet-alert 10129] V2491 Cyg dramatic fading


>   As reported by Martin Nicholson, V2491 Cyg has dramatically faded
> following the rebrightening.  The behavior is thus very similar to
> the rebrightening phenomena in V2362 Cyg and V1493 Aql.  Multicolor
> photometry (especially infrared to see if dust formation occurs)
> and spectroscopy are urgently requested.
>
>  YYYYMMDD(UT)   mag  observer
>  20080420.714  9.82V  (Kazuhiro Nakajima)
>  20080420.716  8.67Rc  (Kazuhiro Nakajima)
>  20080420.719  9.90B  (Kazuhiro Nakajima)
>  20080420.722  10.08y  (Kazuhiro Nakajima)
>  20080421.023  10.043C  (Lubomir Urbancok)
>  20080421.081    99  (Bjorn H. Granslo)
>  20080421.702  10.12y  (Kazuhiro Nakajima)
>  20080421.705  9.86V  (Kazuhiro Nakajima)
>  20080421.707  8.78Rc  (Kazuhiro Nakajima)
>  20080421.711  9.93B  (Kazuhiro Nakajima)
>  20080421.988    99  (Bjorn H. Granslo)
>  20080422.408  9.80V  (Martin Nicholson)
>  20080422.408  9.85B  (Martin Nicholson)
>  20080423.051    97  (Bjorn H. Granslo)
>  20080424.000    98  (Bjorn H. Granslo)
>  20080424.051  9.342C  (Lubomir Urbancok)
>  20080424.125   101  (Jose Ripero)
>  20080424.689    98  (Yutaka Maeda)
>  20080424.690  9.84y  (Kazuhiro Nakajima)
>  20080424.692  9.59V  (Kazuhiro Nakajima)
>  20080424.696  8.68Rc  (Kazuhiro Nakajima)
>  20080424.698  9.66B  (Kazuhiro Nakajima)
>  20080424.778    98  (Susumu Takahashi)
>  20080425.014    98  (Bjorn H. Granslo)
>  20080425.016    94  (Laurent Bichon)
>  20080425.444  9.57V  (Martin Nicholson)
>  20080425.444  9.63B  (Martin Nicholson)
>  20080425.765  9.86y  (Kazuhiro Nakajima)
>  20080425.769  9.58V  (Kazuhiro Nakajima)
>  20080425.770  8.68Rc  (Kazuhiro Nakajima)
>  20080425.781  9.67B  (Kazuhiro Nakajima)
>  20080425.929    95  (Laurent Bichon)
>  20080426.374  9.56V  (Martin Nicholson)
>  20080426.376  9.60B  (Martin Nicholson)
>  20080427.058    98  (Georg Comello)
>  20080427.083    99  (Wolfgang Kriebel)
>  20080428.403  11.13V  (Martin Nicholson)
>  20080428.403  11.17B  (Martin Nicholson)