A tale of two GRB-SNe at a common redshift of z = 0.54
Abstract
We present ground-based and HST optical observations of the optical transients (OTs) of long-duration Gamma Ray Bursts (GRBs) 060729 and 090618, both at a redshift of z = 0.54. For GRB 060729, bumps are seen in the optical light curves (LCs), and the late-time broadband spectral energy distributions (SEDs) of the OT resemble those of local type Ic supernovae (SNe). For GRB 090618, the dense sampling of our optical observations has allowed us to detect well-defined bumps in the optical LCs, as well as a change in colour, that are indicative of light coming from a core-collapse SN. The accompanying SNe for both events are individually compared with SN1998bw, a known GRB-supernova, and SN1994I, a typical type Ic supernova without a known GRB counterpart, and in both cases the brightness and temporal evolution more closely resemble SN1998bw. We also exploit our extensive optical and radio data for GRB 090618, as well as the publicly-available SWIFT -XRT data, and discuss the properties of the afterglow at early times. In the context of a simple jet-like model, the afterglow of GRB 090618 is best explained by the presence of a jet-break at t-to > 0.5 days. We then compare the rest-frame, peak V -band absolute magnitudes of all of the GRB and X-Ray Flash (XRF)-associated SNe with a large sample of local type Ibc SNe, concluding that, when host extinction is considered, the peak magnitudes of the GRB/XRF-SNe cannot be distinguished from the peak magnitudes of non-GRB/XRF SNe.
Cite
@article{arxiv.1012.1466,
title = {A tale of two GRB-SNe at a common redshift of z = 0.54},
author = {Z. Cano and D. Bersier and C. Guidorzi and R. Margutti and K. M Svensson and S. Kobayashi and A. Melandri and K. Wiersema and A. Pozanenko and A. J. van der Horst and G. G. Pooley and A. Fernandez-Soto and A. J. Castro-Tirado and A. de Ugarte Postigo and M. Im and A. P. Kamble and D. Sahu and J. Alonso-Lorite and G. Anupama and J. L. Bibby and M. J. Burgdorf and N. Clay and P. A. Curran and T. A. Fatkhullin and A. S. Fruchter and P. Garnavich and A. Gomboc and J. Gorosabel and J. F. Graham and U. Gurugubelli and J. Haislip and K. Huang and A. Huxor and M. Ibrahimov and Y. Jeon and Y-B. Jeon and K. Ivarsen and D. Kasen and E. Klunko and C. Kouveliotou and A. LaCluyze and A. J. Levan and V. Loznikov and P. A. Mazzali and A. S. Moskvitin and C. Mottram and C. G. Mundell and P. E. Nugent and M. Nysewander and P. T. O'Brien and W. -K. Park and V. Peris and E. Pian and D. Reichart and J. E. Rhoads and E. Rol and V. Rumyantsev and V. Scowcroft and D. Shakhovskoy and E. Small and R. J. Smith and V. V. Sokolov and R. L. C. Starling and I. Steele and R. G. Strom and N. R. Tanvir and Y. Tsapras and Y. Urata and O. Vaduvescu and A. Volnova and A. Volvach and R. A. M. J. Wijers and S. E. Woosley and D. R. Young},
journal= {arXiv preprint arXiv:1012.1466},
year = {2015}
}
Comments
Accepted for publication in MNRAS on Dec 07, 2010. 18 pages, 12 figures, 9 tables