Photometric evolution of SNe Ib/c 2004ao, 2004gk, and 2006gi

Abstract

Photometric observations of three core collapse supernovae (SNe 2004ao, 2004gk, and 2006gi), covering about 200 days of evolution, are presented and analyzed. The photometric behavior of the three objects is consistent with their membership in the envelope-stripped Type Ib/c class. Pseudobolometric light curves are constructed. The corresponding measured e-folding times are found to be faster compared to the 56Co decay (i.e., 111.3 days), suggesting that a proportion of γ-rays increasing with time have escaped without thermalization, owing to the low-mass nature of the ejecta. SN2006gi has almost identical post-maximum decline phase luminosities as SN1999ex and found to be similar to both SNe 1999dn and 1999ex in terms of the quasi-bolometric shape, placing it among the fast decliner Ib objects. SN2004ao appears to fit within the slow decliner Ib SNe. SNe 2004ao and 2004gk display almost identical luminosities in the [50-100] day time interval, similar to SN1993J. A preliminary simplified γ-ray deposition model is described and applied to the computed pseudobolometric light curves, allowing one to find a range in the ejecta and 56Ni masses. The optical and quasi-bolometric light curves and the B - V color evolution of SN2004gk are found to show a sudden drop after day 150. Correlating this fact to dust formation is premature and requires further observational evidence. © 2011. The American Astronomical Society. All rights reserved.