[vsnet-newvar 1530] (fwd) New variable star probably in M31 galaxy

[Taichi Kato <tkato@kusastro.kyoto-u.ac.jp>]

(fwd) New variable star probably in M31 galaxy

   Wouldn't it be a nova in M31?

Date: Tue, 27 Aug 02 15:00:11 CET
From: ok2rea@prgate.sci.muni.cz (Kamil Hornoch)
Subject: New variable star probably in M31 galaxy

Dear colleagues, I will send message about discovery of a new variable star
to vsnet-newvar mailing list.
Many thanks,
               Kamil Hornoch


Dear colleagues,
                 I inform you about a new variable
star in M31 or in foreground. I found the variable star
with CCD observations with 0.35-m RL + CCD ST-6V + R filter
made by me on 16./17.8. 2001, 3./4.8. 2002, 17./18.8. 2002,
25./26.8. 2002, 26./27.8. 2002 and from Digitized Sky Survey II
red plates.
On the DSS-II red plates (taken at epoch 1986.907 and 1989.749)
the star is not present (no object brighter than R=20.5 mag).
Closest star on the DSS-II red plates is about 2"-3" from 
position of the new variable with R-magnitude about 20.5-21 mag.

I measured precise positions of the new variable from my CCD images:

00h 42m 30.9s +/- 0.1s
+41d 06' 13" +/- 1"
(Equinox J2000.)

My photometry from 5 nights gave:

2001-08-16.958  R=17.9 mag
2002-08-04.013  R=17.0 mag
2002-08-17.952  R=17.1 mag
2002-08-25.859  R=18.1 mag
2002-08-26.850  R=18.0 mag

On August 26.84 UT Peter Kusnirak, Ondrejov observatory,
Czech Republic, made on my request 2x300s exposures using
0.65-m RL + CCD + R filter and 2x300s exposures with V
filter. Atmospheric conditions was no good, but these
snapshots confirmed drop of brightness of the star.
Also shows, that V-R index of this variable is larger than of
surrounding stars with comparable brightness, roughly estimated
of about 1-1.5 mag.
Probably large amplitude and large V-R index suggest, that it
may be a Mira-type variable.

Observations of this star by me will be continued.

The variable is not present in the most recent GCVS vol. V nor
in newvar.cat. Closest stars presented in newvar.cat
(designated MLAxxx em, where xxx is 3-places number of the star)
are more than 26" from the new variable.

Best regards,
                  Kamil Hornoch

                  Lelekovice 393
                  664 31 Lelekovice
                  Czech Republic
                  hornoch@astro.sci.muni.cz

VSNET Home Page

Return to Daisaku Nogami

---

vsnet-adm@kusastro.kyoto-u.ac.jp