2008CBET.1353....1Y

F. Yuan, University of Michigan; R. Quimby, California Institute of Technology; D. Chamarro, M. D. Sisson, and C. Akerlof, University of Michigan; and J. C. Wheeler, University of Texas, on behalf of the ROTSE collaboration, report the discovery of a supernova (mag about 17.7) in unfiltered CCD images taken on Apr. 22.14 UT with the 0.45-m ROTSE-IIIb telescope at McDonald Observatory. The new object, designated 2008bz, is located at R.A. = 12h38m57s.74, Decl. = +11o07'46".2 (equinox 2000.0; uncertainty < 1"), which is 5".7 west and 3".8 south of the center the apparent host galaxy (2MASX J12385810+1107502). A finding chart for 2008bz is posted at website URL http:/www.rotse.net/rsvp/j123857.7+110746/j123857.7+110746.jpg. A spectrum (range 420-890 nm) of 2008bz, obtained on Apr. 23.13 with the 9.2-m Hobby- Eberly Telescope (+ Marcario Low-Resolution Spectrograph) by S. Rostopchin and F. Deglman, shows it to be a type-Ia supernova. The spectra are similar to those of SN 1992A around maximum light (Kirshner et al. 1993, Ap.J. 415, 589). Correcting for the Sloan Digital Sky Survey redshift of the host galaxy (z = 0.06), the minimum of the Si II 635.5-nm feature is blushifted by 11300 km/s. CORRIGENDUM. On CBET 1350, SN 2008by, line 14, FOR about five days after explosion READ about five days after maximum light