Discovery of SN 2009nz Associated with GRB 091127
Abstract
We report SMARTS, Gemini and Swift-UVOT observations of the optical transient (OT) associated with gamma-ray burst (GRB) 091127, at redshift 0.49, taken between 0.9 hr and 102 days following the Swift trigger. In our early-time observations, the OT fades in a manner consistent with previously observed GRB afterglows. However, after 9 days post-burst, the OT is observed to brighten for a period of ~2 weeks, after which the source resumes fading. A comparison of this late-time "bump" to SN 1998bw (the broad-lined Type Ic supernova associated with GRB 980425), and several other GRB supernovae (SNe), indicates that the most straightforward explanation is that GRB 091127 was accompanied by a contemporaneous SN (SN 2009nz) that peaked at a magnitude of M_V=-19.0+/-0.2. SN 2009nz is globally similar to other GRB supernovae, but evolves slightly faster than SN 1998bw and reaches a slightly dimmer peak magnitude. We also analyze the early-time UV-optical-IR spectral energy distribution of the afterglow of GRB 091127 and find that there is little to no reddening in the host galaxy along the line-of-slight to this burst.
Cite
@article{arxiv.1005.4961,
title = {Discovery of SN 2009nz Associated with GRB 091127},
author = {B. E. Cobb and J. S. Bloom and D. A. Perley and A. N. Morgan and S. B. Cenko and A. V. Filippenko},
journal= {arXiv preprint arXiv:1005.4961},
year = {2015}
}
Comments
minor edits, accepted by ApJ Letters