SN 2009bb: a Peculiar Broad-Lined Type Ic Supernova
Abstract
Ultraviolet, optical, and near-infrared photometry and optical spectroscopy of the broad-lined Type Ic supernova (SN) 2009bb are presented, following the flux evolution from -10 to +285 days past B-band maximum. Thanks to the very early discovery, it is possible to place tight constraints on the SN explosion epoch. The expansion velocities measured from near maximum spectra are found to be only slightly smaller than those measured from spectra of the prototype broad-lined SN 1998bw associated with GRB 980425. Fitting an analytical model to the pseudo-bolometric light curve of SN 2009bb suggests that 4.1+-1.9 Msun of material was ejected with 0.22 +-0.06 Msun of it being 56Ni. The resulting kinetic energy is 1.8+-0.7x10^52 erg. This, together with an absolute peak magnitude of MB=-18.36+-0.44, places SN 2009bb on the energetic and luminous end of the broad-lined Type Ic (SN Ic) sequence. Detection of helium in the early time optical spectra accompanied with strong radio emission, and high metallicity of its environment makes SN 2009bb a peculiar object. Similar to the case for GRBs, we find that the bulk explosion parameters of SN 2009bb cannot account for the copious energy coupled to relativistic ejecta, and conclude that another energy reservoir (a central engine) is required to power the radio emission. Nevertheless, the analysis of the SN 2009bb nebular spectrum suggests that the failed GRB detection is not imputable to a large angle between the line-of-sight and the GRB beamed radiation. Therefore, if a GRB was produced during the SN 2009bb explosion, it was below the threshold of the current generation of gamma-ray instruments.
Cite
@article{arxiv.1011.6126,
title = {SN 2009bb: a Peculiar Broad-Lined Type Ic Supernova},
author = {Giuliano Pignata and Maximilian Stritzinger and Alicia Soderberg and Paolo Mazzali and M. M. Phillips and Nidia Morrell and J. P. Anderson and Luis Boldt and Abdo Campillay and Carlos Contreras and Gastón Folatelli and Francisco Förster and Sergio González and Mario Hamuy and Wojtek Krzeminski and José Maza and Miguel Roth and Francisco Salgado Emily M. Levesque and Armin Rest and J. Adam Crain and Andrew C. Foster and Joshua B. Haislip and Kevin M. Ivarsen and Aaron P. LaCluyze and Melissa C. Nysewander and Daniel E. Reichart},
journal= {arXiv preprint arXiv:1011.6126},
year = {2015}
}
Comments
Accepted for publication in ApJ