2008CBET.1206....1Y

F. Yuan, University of Michigan; R. Quimby, California Institute of Technology; C. Akerlof, University of Michigan; and J. C. Wheeler, University of Texas, on behalf of the ROTSE collaboration, report the discovery of a supernova in unfiltered CCD images taken with the 0.45-m ROTSE-IIIb telescope at McDonald Observatory on Jan. 4.47 (at mag about 18.2) and 6.28 UT (mag about 18.0). The new object is located at R.A. = 11h25m36s.95, Decl. = +52o08'25".9 (equinox 2000.0; uncertainty < 1"), which is 0".1 west and 1".6 south of a marginally detected galaxy of magnitude r = 21.6 in the Sloan Digital Sky Survey, and lies in the midst of a group of galaxies at redshift 0.034; a finding chart of 2008E can be found at the following website URL: http://www.rotse.net/rsvp/j112537+520826/j112536.9+520826.jpg. A spectrum (range 420-890 nm) of 2008E, obtained on Jan. 7.35 with the 9.2-m Hobby-Eberly Telescope (+ Marcario Low-Resolution Spectrograph) by S. Odewahn and E. Terrazas, shows it to be a type-Ia supernova. The spectrum is similar to that of SN 1992A a few days before maximum light (Kirshner et al. 1993, Ap.J. 415, 589), and is consistent with the redshift of the nearby galaxy cluster.