POSSIBLE SUPERNOVA IN UGC 04958
Zhangwei Jin(Ningbo, Zhejiang, China) and Xing Gao (Urumqi, Xinjiang, China), report the discovery of a possible supernova (mag approximately 17.9) on two 40-s survey images (limiting mag about 19.5)taken by Xing Gao in Xingming ObservationSky Survey(C42) around Nov.05.8703 and Nov.06.8980 UT,2013. using an unfiltered CCD ( + Celestron C14 Schmidt-Cassegrain telescope D=350-mm @f/6.9 ).the new object approximately located at R.A. =09h 21m 08s.25 Decl.=+49°35’33”.8(equinox 2000.0). Which is about 63.7″ east and 34.2″ south of the center of the UGC 04958.
Nothing is visible at this position on archival images taken on Oct.22,2013. (limiting mag 19.2) or on the DSS(POSS2/UKSTU Red) from Mar. 30,1995(limiting mag about 19.8)
NET USNO-A2.0
XM47ZJ C2013 11 05.87031 09 21 08.25 +49 35 33.8 17.9 V C42
XM47ZJ C2013 11 06.89801 09 21 08.25 +49 35 33.7 17.8 V C42
All images can be seen from: http://www.xjltp.com/XOSS/XM47ZJ/XM47ZJ.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. 3705
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 2013gg IN UGC 4958 = PSN J09210825+4935338
Zhangwei Jin, Ningbo, Zhejiang, China; and Xing Gao, Urumqi, Xinjiang,
China, report the discovery of a possible supernova (mag approximately 17.9)
on two 40-s unfiltered CCD survey images (limiting mag about 19.5) taken by
Gao in the course of the Xingming Sky Survey around Nov. 5.870 and 6.898 UT
using a 0.35-m Celestron C14 reflector at Mt. Nanshan. The new object is
approximately located at R.A. = 9h21m08s.25, Decl. = +49d35’33”.8 (equinox
2000.0), which is about 63″.7 east and 34″.2 south of the center of UGC 4958.
Nothing is visible at this position on a Digitized Sky Survey image from 1995
Mar. 30 (limiting red mag about 19.8). The discovery images are posted at
website URL http://www.xjltp.com/XOSS/XM47ZJ/XM47ZJ.htm. The variable was
designated PSN J09210825+4935338 when it was posted at the Central Bureau’s
TOCP webpage and is here designated SN 2013gg based on the spectroscopic
confirmation reported below. Additional CCD magnitudes for 2013gg: 2013 Oct.
22, [19.2 (Jin and Gao); Nov. 7.118, 17.7 (Gianluca Masi, Francesca Nocentini,
and Patrick Schmeer; remotely using a 36-cm robotic telescope near Ceccano,
Italy; position end figures 08s.22, 33″.8); 7.188, 18.1 (Federica Luppi and
Luca Buzzi, Varese, Italy; 0.36-m f/7.1 reflector; position end figures 08s.26,
33″.2; reference stars from CMC-14 catalogue; image posted at website URL
http://www.astrogeo.va.it/pub/TOCP/PSN_U04958.jpg); 7.380, 18.4 (Joseph
Brimacombe, Cairns, Australia; remotely with a 51-cm RCOS telescope +
STXL-6303 camera located at the New Mexico Skies observatory near Mayhill,
NM, USA; position end figures 08s.31, 33″.7; image posted at website URL
http://www.flickr.com/photos/43846774@N02/10741553623/).
D. Milisavljevic, Harvard-Smithsonian Center for Astrophysics; and S.
Gottilla, MMT Observatory, report that a low-dispersion spectrogram (range
335-855 nm), obtained on Nov. 8.4 UT with the 6.5-m MMT telescope (+ Blue
Channel), shows PSN J09210825+4935338 = SN 2013gg to be a young type-II
supernova. Cross-correlation with a library of supernova spectra using the
“Supernova Identification” code (SNID; Blondin and Tonry 2007, Ap.J. 666,
1024) shows a reasonable match with the type-IIP event 2006bp at four days
after maximum light. Using a redshift of z = 0.0274 for the host galaxy, UGC
4958 (from the Sloan Digital Sky Survey, DR2, 2004; via NED), they estimate
the minimum of the H_alpha P-Cyg absorption to be blueshifted by approximately
13000 km/s.
NOTE: These ‘Central Bureau Electronic Telegrams’ are sometimes
superseded by text appearing later in the printed IAU Circulars.
(C) Copyright 2013 CBAT
2013 November 11 (CBET 3705) Daniel W. E. Green