[IAUC] CBET 3250: 20121009 : PROBABLE NOVA IN M33 = PNV J01325723+3024260

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                                                  Electronic Telegram No. 3250
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)
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Prepared using the Tamkin Foundation Computer Network


PROBABLE NOVA IN M33 = PNV J01325723+3024260
     W. Zheng, University of Michigan; F. V. Ferrante, Southern Methodist
University; R. Quimby, IPMU, University of Tokyo; J. Vinko, University of
Szeged; G. H. Marion, Harvard-Smithsonian Center for Astrophysics; G. Dhungana
and Bob Kehoe, Southern Methodist University; A. Romadan and C. Akerlof,
University of Michigan; F. Yuan, Australian National University; and J. C.
Wheeler and E. Chatzopoulos, University of Texas, on behalf of the ROTSE
collaboration, report the discovery of an optical transient in the outskirts
of M33 in unfiltered CCD images taken with the ROTSE-IIIb telescope at
McDonald Observatory.  The object is located at R.A. = 1h32m57s.28, Decl. =
+30o24'27".3 (equinox 2000.0; uncertainty < 1"), which is 15'10" west and
11'32" south of the core of M33.  Available approximate ROTSE magnitudes for
the variable (calibrated relative to USNO-B1.0-catalogue magnitudes):  Sept.
23 and earlier, [18; Oct. 3.17 UT, 17.1; 4.17, 16.6.  A finding chart for
the variable can be viewed at website URL http://tinyurl.com/9g8twg7.
     A spectrogram, obtained on Oct. 5.19 UT with the 9.2-m Hobby-Eberly
Telescope (+ Marcario Low-Resolution Spectrograph) by J. Caldwell, shows a
blue continuum with many narrow absorption lines, including H-alpha, H-beta,
H-gamma, and O I features.  These features appear blueshifted by about 400
km/s in the rest frame of M33.  The spectrum is also contaminated by features
at zero redshift, including Na I D at -78 km/s.  Despite the lack of either
emission lines or P-Cyg features, the spectrum may be consistent with that of
a very young nova, shortly after outburst.  The observed magnitude,
corresponding to absolute mag about -8, is consistent with the expected
brightness of a young nova.

     An independent discovery of the possible nova was reported by Koichi
Nishiyama (Kurume, Japan) and Fujio Kabashima (Miyaki, Japan) on eight 40-s
unfiltered CCD frames (limiting magnitude 19.1) taken around Oct. 6.661 UT
using a Meade 200R 0.40-m f/9.8 reflector (+ SBIG STL1001E camera).  They
reported the object to be of mag 17.2 and located at R.A. = 1h32m57s.23,
Decl. = +30d24'26".0 (equinox 2000.0), which is 693" west and 911" south of
the center of the galaxy M33.  They add that nothing is visible at this
position on their frames taken on Oct. 2.535 (limiting magnitude 18.8), but
that it was visible at mag 15.8 on a prediscovery frame taken on Oct. 4.583.
Also, nothing is visible at that position Digitized Sky Survey plates taken
on 1991 Oct. 5 (limiting red mag 19.5) and 1989 Dec. 4 (limiting infrared
mag 19.5).   The variable was designated PNV J01325723+3024260 when it was
posted at the Central Bureau's TOCP webpage.  D. Denisenko, V. Yurkov, E.
Sinyakov, E. Gorbovskoy, and V. Lipunov (on behalf of the large MASTER team)
report an auto-detection of the apparent nova in two unfiltered 60-s images
taken with the MASTER-Amur telescopic system, reporting magnitudes 16.0 on
Oct. 5.534 and 16.4 on Oct. 5.565, adding that nothing was visible in a red
reference image taken on Jan. 6.436 (limiting mag 19.1); they measured
position end figures 57s.28, 24".8.  The MASTER-Amur images are posted at
website URL http://master.sai.msu.ru/static/OT/013257.28302424.8.png.


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                         (C) Copyright 2012 CBAT
2012 October 9                   (CBET 3250)              Daniel W. E. Green