2011ATel.3398....1S

The PTF (ATEL #1964, #3253; http://www.astro.caltech.edu/ptf/; Law et al. 2009, PASP, 121, 1395; Rau et al. 2009, PASP, 121, 1334) reports the discovery of a new supernova in M51. This object was independently discovered first by A. Riou and reported as PSN J13303600+4706330. PTF discoveries are made by autonomous PTF software, as well as by the Galaxy Zoo Supernova Project (Smith et al. 2011, MNRAS, 412, 1309; http://supernova.galaxyzoo.org

Name | RA (J2000) | Dec (J2000) | Discovery | Mag | Redshift | Type

| Spec. | Phase | Instrument | Notes PTF11eon | 13 30 05.08 | +47 10 11.2 | Jun 01.19 | 13.5 | 0.002 | SN | Jun. 2 | | Keck I+ LRIS | exact magnitude uncertain due to saturation

The spectrum shows a relatively blue continuum, with well-developed P-Cygni profiles in the Balmer series. After removal of the host-galaxy recession velocity of 600 km/s (Rush, et al. 1996, ApJ, 473, 130), the minimum of the H-alpha absorption is blueshifted by about 17,600 km/s.

PTF is a collaboration of Caltech, LCOGT, the Weizmann Institute, LBNL, Oxford, Columbia, IPAC, and Berkeley.