Monday, April 30, 2012

1204.6109 (Takashi J. Moriya et al.)

Light Curve Modeling of Superluminous Supernova 2006gy: Collision between Supernova Ejecta and Dense Circumstellar Medium    [PDF]

Takashi J. Moriya, Sergei I. Blinnikov, Nozomu Tominaga, Naoki Yoshida, Masaomi Tanaka, Keiichi Maeda, Ken'ichi Nomoto
We show model light curves of superluminous supernova 2006gy on the assumption that the supernova is powered by the collision of supernova ejecta and its dense circumstellar medium. The initial conditions are constructed based on the shock breakout condition, assuming that the circumstellar medium is dense enough to cause the shock breakout within it. We perform a set of numerical light curve calculations by using a one-dimensional multigroup radiation hydrodynamics code STELLA. Our model reproduces the light curve of SN 2006gy. A best light curve is obtained when the circumstellar medium around the progenitor of SN 2006gy is about 18 Msun (the average mass-loss rate ~ 0.4 Msun/yr). The progenitor of SN 2006gy is likely a very massive star. The density profile of the circumstellar medium is not well constrained by the light curve only, but our modeling disfavors the circumstellar medium formed by a steady mass loss. The ejecta mass is estimated to be comparable to or less than 18 Msun and the explosion energy is expected to be more than 4*10^{51} erg. No 56Ni is required to explain the early light curve. We find that the multidimensional effect, e.g., the Rayleigh-Taylor instability, which is expected to take place in the cool dense shell between the supernova ejecta and the dense circumstellar medium, is important in understanding the light curve powered by the shock interaction. We also show the evolution of the optical and near-infrared model light curves of high-redshift superluminous supernovae. The model can be used to identify SN 2006gy-like superluminous supernovae in the future optical and near-infrared transient surveys.
View original: http://arxiv.org/abs/1204.6109

No comments:

Post a Comment