Christopher J. White, Mansi M. Kasliwal, Peter E. Nugent, Avishay Gal-Yam, D. Andrew Howell, Mark Sullivan, Ariel Goobar, Anthony L. Piro, Joshua S. Bloom, Shrinivas R. Kulkarni, Russ R. Laher, Frank Masci (+11 others)
2015 Astrophysical Journal  
Since the discovery of the unusual prototype SN 2002cx, the eponymous class of low-velocity, hydrogen-poor supernovae has grown to include at most another two dozen members identified from several heterogeneous surveys, in some cases ambiguously. Here we present the results of a systematic study of 1077 hydrogen-poor supernovae discovered by the Palomar Transient Factory, leading to nine new members of this peculiar class. Moreover we find there are two distinct subclasses based on their
more » ... scopic, photometric, and host galaxy properties: The "SN 2002cx-like" supernovae tend to be in later-type or more irregular hosts, have more varied and generally dimmer luminosities, have longer rise times, and lack a Ti II trough when compared to the "SN 2002es-like" supernovae. None of our objects show helium, and we counter a previous claim of two such events. We also find that these transients comprise 5.6+17-3.7% (90% confidence) of all SNe Ia, lower compared to earlier estimates. Combining our objects with the literature sample, we propose that these subclasses have two distinct physical origins.
doi:10.1088/0004-637x/799/1/52 fatcat:mblko44j4nf3dkpbosmy4t2lbi