金彰伟2月18日上午在检看稍早拍摄的星系图片时,发现PGC55040有疑似超新星爆发,查看历史图片发现2月14日该目标已经很明显,由于2月13日也拍摄过该星系,当时检看时以为是杂点而未注意,2月14日是重拍该星系而金彰伟未检看未及时发现该目标,15日检看的图片质量不好又未见目标,16日也可见该目标,但由于14日同样的原因未检看图片。
POSSIBLE SUPERNOVA IN PGC 55040
Zhangwei Jin(Ningbo, Zhejiang, China) and Xing Gao (Urumqi, Xinjiang, China), report the discovery of a possible supernova (mag approximately 17.9) on a 40-s survey image (limiting mag about 19.5)taken by Xing Gao in Xingming ObservationSky Survey(C42) around Feb .17.93912 UT,2012. using a unfilted CCD ( + Celestron C14 Schmidt-Cassegrain telescope D=350-mm @f/6.9 ).the new object approximately located at R.A. =15h 25m 08s.52Decl.=+37°57’49”.4(equinox 2000.0). Which is about 30.9″ east and 12.9″ north of the center of the PGC 55040.
Nothing is visible at this position at this position on archival images taken on Feb.11 (limiting mag 19.0) or on the DSS(POSS2/UKSTU Red) from Apr. 17,1993(limiting mag about 19.8)
NET UCAC-3
XM37ZJ C2012 02 14.91505 15 25 08.46 +37 57 49.4 18.7 V C42
XM37ZJ C2012 02 17.93912 15 25 08.52 +37 57 49.4 18.2 V C42
All images can be seen from: http://www.xjltp.com/XOSS/XM37ZJ/XM37ZJ.htm
C42,Xingming Observatory, Mt. Nanshan. Observers Z.Jin, X.Gao ,Measurers Z.Jin 0.35-m f/6.9 Schmidt-Cassegrain telescope and CCD.
Electronic Telegram No. 3044
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@eps.harvard.edu (alternate cbat@iau.org)
URL http://www.cbat.eps.harvard.edu/index.html
Prepared using the Tamkin Foundation Computer Network
SUPERNOVA 2012as IN UGC 9842 = PSN J15250852+3757494
Zhangwei Jin (Ningbo, Zhejiang, China) and Xing Gao (Urumqi, Xinjiang,
China) report the discovery of a possible supernova (mag approximately 17.9)
on an unfiltered 40-s survey image (limiting mag about 19.5) taken by Xing Gao
in the course of the Xingming Sky Survey around Feb. 17.939 UT using a
Celestron C14 Schmidt-Cassegrain telescope at Mt. Nanshan. The new object is
approximately located at R.A. = 15h25m08s.52, Decl. = +37d57’49”.4 (equinox
2000.0), which is about 30″.9 east and 12″.9 north of the center of UGC 9842 =
PGC 55040. The variable was designated PSN J15250852+3757494 when it was
posted at the Central Bureau’s TOCP webpage and is here designated SN 2012as
based on the spectroscopic confirmation reported below. Additional magnitudes
for 2012as: 1993 Apr. 17, [19.8 (Digitized Sky Survey, red plate; via Jin and
Gao); 2012 Feb. 11, [19.0 (Jin and Gao); 14.915, 18.7 (Jin and Gao; pre-
discovery; position end figures 08s.46, 49″.4); 19.413, 17.6 (J. Brimacombe,
Cairns, Australia; remotely using a 51-cm RCOS telescope + STL11K camera +
luminance filter at the New Mexico Skies Observatory near Mayhill, NM, U.S.A.;
position end figures 08s.58, 50″.2); 22.184, 17.6 (Federica Luppi and Luca
Buzzi, Varese, Italy; 0.38-m f/6.8 reflector; position end figures 08s.52,
49″.7; reference stars from CMC-14 catalogue). The Xingming images are posted
at website URL http://www.xjltp.com/XOSS/XM37ZJ/XM37ZJ.htm. Brimacombe’s
image is posted at URL http://www.flickr.com/photos/43846774@N02/6906737045/.
Luppi and Buzzi have posted their image at the following website URL:
http://www.astrogeo.va.it/pub/TOCP/PSN_P55040.jpg.
M. Fraser, T.-W. Chen, S. J. Smartt, and R. Kotak, Queen’s University,
Belfast, report that they obtained a spectrum (range 530-975 nm; resolution
about 1.3 nm) of PSN J15250852+3757494 = SN 2012as on Mar. 4.28 UT with the
4.2-m William Herschel Telescope (+ ISIS). The spectrum appears similar to
that of a type-IIn supernova, with a blue continuum and a narrow emission
feature from H_alpha. Note that, at the distance of the host galaxy, the
supernova has an absolute magnitude of -18, which strongly disfavors this
being a supernova impostor.
NOTE: These ‘Central Bureau Electronic Telegrams’ are sometimes
superseded by text appearing later in the printed IAU Circulars.
(C) Copyright 2012 CBAT
2012 March 5 (CBET 3044) Daniel W. E. Green