Browsing by Author "Garradd, G."

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    Supernova 2011hb = PSN J23275551+0846457
    (2011) Howerton, S.; Drake, A. J.; Djorgovski, S. G.; Mahabal, A.; Graham, M. J.; Williams, R.; Prieto, J. L.; Catelan, Marcio; McNaught, R. H.; Garradd, G.; Beshore, E. C.; Larson, S. M.; Christensen, E.; Elenin, L.; Jacques, C.; Pimentel, E.
    Report the discovery of an apparent supernova in public images from the Catalina Sky Survey (CSS). SN 2011 UT R.A. (2000.0) Decl. Mag. Offset 2011hb Oct. 24.24 23 27 55.51 + 8 46 45.7 18.8 6".7 W, 25".2 S The variable was designated PSN J23275551+0846457 when it was posted at the Central Bureau's TOCP webpage and is here designated SN 2011hb based on the spectroscopic confirmation reported below. Additional unfiltered CCD magnitudes for 2011hb: Oct. 6.19 UT, [20.5 (CSS); 16.24, 20.3 (CSS); 26.082, 17.3 (L. Elenin, remotely using a 0.45-m f/2.8 astrograph at the ISON-NM Observatory near Mayhill, NM, USA; limiting mag about 19.7; position end figures 55.s.55, 45".5; NOMAD reference stars; image posted at website URL http://spaceobs.org/images/TOCP/PSNJ23275551+0846457.jpg); 26.142, 17.5 (C. Jacques and E. Pimentel, Belo Horizonte, Brazil; remotely using the GRAS G05 telescope in New Mexico; position end figures 55s.59, 45".2; UCAC2 reference stars; limiting magnitude 19.0; image posted at the following website URL: http://ceamig-rea.net/tocp/ngc7674_tocp.jpg). G. H. Marion, Harvard-Smithsonian Center for Astrophysics (CfA), on behalf of the CfA Supernova Group, report that a spectrum (range 340-740 nm) of PSN J23275551+0846457 = SN 2011hb was obtained on Oct. 28 UT by P. Berlind with the F. L. Whipple Observatory 1.5-m telescope (+ FAST). Cross-correlation with a library of supernova spectra using the "Supernova Identification" code (SNID; Blondin and Tonry 2007, Ap.J. 666, 1024) shows that 2011hb is a type-Ia supernova several days before maximum light. SNID finds that the best fit is to a template from the normal type-Ia supernova 2005cf at -10 days. The Si II 635.5-nm feature is broad and asymmetrical; an estimated redshift of z = 0.028924 for NGC 7674 (Nishiura et al. 2000, A.J. 120, 1691) is used to measure the velocity at the minimum of this feature to be about 14700 km/s