Discovery of a supernova ROTSE3 J235413+272433
ATel #1280; F. Yuan (U. Mich.), R. Quimby (Caltech), J. Aretakis, C. Akerlof (U. Mich.) and J. C. Wheeler (U. Texas) on behalf of the ROTSE collaboration; The Nearby Supernova Factory
on 14 Nov 2007; 22:31 UT
Credential Certification: Fang Yuan (email@example.com)
Subjects: Optical, Nova, Supernovae
Referred to by ATel #: 1420
We report the discovery of a supernova, located at RA: 23:54:12.98 Dec: +27:24:33.4 (J2000 uncertainty <1"), in unfiltered CCD images taken by the 0.45m ROTSE-IIIb telescope at McDonald Observatory, Texas. The supernova was discovered at ~17.4 mag on Nov 13.17 UT and was observed at ~17.0 mag on Nov 14.12 UT. It is 11.9" east and 1.1" north from the center of its apparent host, an anonymous galaxy seen in DSS. A finding chart of the supernova can be found at: http://www.rotse.net/transients/j2354+2724/j235413+272433.jpg
A spectrum obtained by the Nearby Supernova Factory (ATEL #1241) on Nov. 14.3 with the SuperNova Integral Field Spectrograph on the University of Hawaii 2.2-meter telescope shows it to be a young Type Ia, easily a week before peak brightness. The redshift is undetermined as no lines from the host are present in the IFU. However, compared to other supernova spectra at similar epochs, cz < 3000 km/s. The Ca II IR triplet and H&K lines are quite broad, with the former showing absorption over 90 nm.