Physical Sciences and Mathematics Commons^™

Sn 2012cg: Evidence For Interaction Between A Normal Sn Ia And A Non-Degenerate Binary Companion, G. H. Marion, Peter J. Brown, Jozsef Vinkó, Jeffrey M. Silverman, David J. Sand, Peter Challis, Robert P. Kirshner, J. Craig Wheeler, Perry Berlind, Warren R. Brown, Michael L. Calkins, Yssavo Camacho, Govinda Dhungana, Ryan J. Foley, Andrew S. Friedman, Melissa L. Graham, D. Andrew Howell, Eric Y. Hsiao, Jonathan M. Irwin, Saurabh W. Jha, Robert Kehoe, Lucas M. Macri, Keiichi Maeda, Kaisey Mandel, Curtis Mccully, Viraj Pandya, Kenneth J. Rines, Steven Wilhelmy, Weikang Zheng

Physics & Astronomy

We report evidence for excess blue light from the Type Ia supernova (Sn Ia) SN 2012cg at 15 and 16 days before maximum B-band brightness. The emission is consistent with predictions for the impact of the supernova on a non-degenerate binary companion. This is the first evidence for emission from a companion to a normal SN Ia. Sixteen days before maximum light, the color of SN 2012cg is 0.2 mag bluer than for other normal SN Ia. At later times, this supernova has a typical SN Ia light curve, with extinction-corrected mag and . Our data set is extensive, …