SN. 2012cg: EVIDENCE FOR INTERACTION BETWEEN A NORMAL SN Ia AND A NON-DEGENERATE BINARY COMPANION Academic Article uri icon

abstract

  • ABSTRACT We report evidence for excess blue light from the Type Ia supernova (Sn Ia) SN2012cg 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 SNIa. Sixteen days before maximum light, the B − V ?> color of SN2012cg is 0.2 mag bluer than for other normal SNIa. At later times, this supernova has a typical SNIa light curve, with extinction-corrected M B = − 19.62 ± 0.02 ?> mag and m{Delta }}{m}_{15}(B)=0.86pm 0.02$?> Δ m 15 ( B ) = 0.86 ± 0.02 ?> . Our data set is extensive, with photometry in seven filters from five independent sources. Early spectra also show the effects of blue light, and high-velocity features are observed at early times. Near maximum, the spectra are normal with a silicon velocity v Si=10,500 km s1. Comparing the early data with models by Kasen favors a main-sequence companion of about six solar masses. It is possible that many other SN Ia have main-sequence companions that have eluded detection because the emission from the impact is fleeting and faint.

published proceedings

  • ASTROPHYSICAL JOURNAL

altmetric score

  • 167.51

author list (cited authors)

  • Marion, G. H., Brown, P. J., Vinko, J., Silverman, J. M., Sand, D. J., Challis, P., ... Zheng, W.

citation count

  • 149

complete list of authors

  • Marion, GH||Brown, Peter J||Vinko, Jozsef||Silverman, Jeffrey M||Sand, David J||Challis, Peter||Kirshner, Robert P||Wheeler, J Craig||Berlind, Perry||Brown, Warren R||Calkins, Michael L||Camacho, Yssavo||Dhungana, Govinda||Foley, Ryan J||Friedman, Andrew S||Graham, Melissa L||Howell, D Andrew||Hsiao, Eric Y||Irwin, Jonathan M||Jha, Saurabh W||Kehoe, Robert||Macri, Lucas M||Maeda, Keiichi||Mandel, Kaisey||McCully, Curtis||Pandya, Viraj||Rines, Kenneth J||Wilhelmy, Steven||Zheng, Weikang

publication date

  • April 2016