[IAUC] CBET 2840: 20110929 : VARIABLE STAR IN PERSEUS: TCP J04283707+3157578

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                                                  Electronic Telegram No. 2840
Central Bureau for Astronomical Telegrams
INTERNATIONAL ASTRONOMICAL UNION
CBAT Director:  Daniel W. E. Green; Hoffman Lab 209; Harvard University;
 20 Oxford St.; Cambridge, MA  02138; U.S.A.
e-mail:  cbatiau en eps.harvard.edu (alternate cbat en iau.org)
URL http://www.cbat.eps.harvard.edu/index.html
Prepared using the Tamkin Foundation Computer Network


VARIABLE STAR IN PERSEUS:  TCP J04283707+3157578
     Timur Krychko and Boris Satovski report their discovery of a previously
unknown variable star (mag 16.9) on unfiltered CCD images (limiting red mag
20.5) obtained on Sept. 22.012 UT using a 0.30-m f/8 reflector at the Astrotel
Observatory, Zelenchukskaya Station, in Russia.  The variable is located at
R.A. = 4h28m37s.07, Decl. = +31d57'57".8 (equinox 2000.0 presumed).  Nothing
is visible at this position on Digitized Sky Survey (DSS) images taken on 1989
Nov. 14 and 1996 Nov. 4, and nothing is visible in 2MASS images obtained on
1999 Nov. 26.  However, the object appears visible at mag 17 on Palomar Sky
Survey images taken on 1955 Oct. 22 and 1992 Oct. 1.  Krychko has posted an
image marking the variable at the following website URL:
http://www.astroalert.su/files/tcp_04283707_3157578_2011-09-22.jpg.
     This variable was designated TCP J04283707+3157578 when it was posted on
the Central Bureau's TOCP webpage.  Joseph Brimacombe, Cairns, Australia,
reports unfiltered CCD mag 19.0 and position end figures 37s.0, 58".1 from
an image taken on Sept. 26.426.

     L. Tomasella, S. Valenti, S. Benetti, and P. Ochner, Osservatorio
Astronomico di Padova, Istituto Nazionale di Astrofisica; and A. Pastorello,
Dipartimento di Astronomia, Universita di Padova, report that a spectrogram of
TCP J04283707+3157578 (range 360-810 nm; resolution 2.2 nm) was obtained on
Sept. 26.10 UT with the Ekar-Copernico 1.82-m telescope (+ AFOSC).  The
spectrum shows a strong H_alpha emission.  Compared to H_alpha, H_beta is weak
but also perceptible:  the possible absorption dips surrounding H_beta could
be the residual effect of the accretion disk following outburst, as is
typically evident in dwarf novae (Szkody et al. 1990, Ap.J. Suppl. 73, 441).
There is a trace of He I emission at 587.6 nm, while all other expected lines
seems to have drowned in the noise.  So the classification of this object
as a cataclysmic variable is plausible.


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                         (C) Copyright 2011 CBAT
2011 September 29                (CBET 2840)              Daniel W. E. Green