Electronic Telegram No. 3978
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 2014dg IN UGC 2855 = PSN J03481978+7007545
     S. Nakano, Sumoto, Japan, reports the discovery by K. Itagaki (Teppo-cho,
Yamagata, Japan) of an apparent supernova (mag 15.4) on an unfiltered CCD
frame (limiting magnitude 19.5) taken on Sept. 11.725 UT using a 0.60-m f/5.7
reflector.  The new object is located at R.A. = 3h48m19s.78, Decl. =
+70d07'54".5 (equinox 2000.0), which is 5".1 west and 3".5 south of the
nucleus of UGC 2855.  Itagaki has posted his discovery image at website URL
http://www.k-itagaki.jp/images/u2855.jpg.  The variable was designated PSN
J03481978+7007545 when it was posted at the Central Bureau's TOCP webpage and
is here designated SN 2014dg based on the spectroscopic confirmation reported
below.  Additional CCD magnitudes for 2014dg:  2011 Oct. 27.872, [19.5
(Itagaki); 2014 Sept. 7.680, [18.5 (Itagaki); 11.81, 16.3 (G. Cortini,
Predappio, Italy; 0.35-m reflector + SXVR H-9 camera; limiting mag 18.5);
11.948, V = 15.9 (S. Kiyota, Kamagaya, Japan; remotely with a 0.32-m f/8
astrograph + Luminance filter + V filter at Nerpio, Spain; image posted at
URL http://meineko.sakura.ne.jp/ccd/PSN_J03481978+7007545.jpg); 12.535, 15.4
(T. Yusa, Y. Suzuki, and K. Kato, Osaki, Japan; 0.30-m f/7 Cassegrain
reflector at the Osaki Lifelong Learning Center; position end figures 19s.93,
54".3; three stacked 60-s frames; limiting mag 17.5); image posted at website
URL http://space.geocities.jp/yusastar77/supernova/PSNinU2855_140912.htm);
12.952, 15.2 (G. Masi, P. Catalano, and P. Schmeer; remotely using a 43-cm
telescope at Ceccano, Italy; position end figures 19s.86, 54".1); 13.453,
14.9 (T. Noguchi, Katori, Chiba-ken, Japan; 0.23-m f/6.3 Schmidt-Cassegrain
reflector; position end figures 19s.94, 54".0; image posted at website URL
http://park8.wakwak.com/~ngc/images/PSNinUGC2855.jpg).

     Y. Moritani, T. Nakaoka, and K. S. Kawabata, Hiroshima University; and M.
Yamanaka, Konan University, obtained a low-resolution optical spectrogram
(range 400-950 nm) of PSN J03481978+7007545 = 2014dg on Sept. 14.6 UT with the
1.5-m Kanata telescope (+ HOWPol) at the Higashi-Hiroshima Observatory.  The
spectrum is consistent with a reddened, pre-maximum type-Ia supernova and
shows a strong Si II 635.5-nm absorption line and the Ca II infrared triplet.
The line velocity of the Si II absorption line is relatively slow (around 9500
km/s).  A comparison with a library of supernova spectra using GELATO
(Harutyunyan et al. 2008, A.Ap. 488, 383) suggests that 2014dg is a good match
to various type-Ia supernovae at a week before maximum light.


NOTE: These 'Central Bureau Electronic Telegrams' are sometimes
      superseded by text appearing later in the printed IAU Circulars.

                         (C) Copyright 2014 CBAT
2014 September 18                (CBET 3978)              Daniel W. E. Green