Constraints on Association of Single-Pulse Gamma-Ray Bursts and Supernovae
Abstract
We explore the hypothesis, similar to one recently suggested by Bloom and colleagues, that some nearby supernovae are associated with smooth, single-pulse gamma-ray bursts, possibly having no emission above ~300 keV. We examine BATSE bursts with durations longer than 2 s, fitting those which can be visually characterized as single-pulse events with a lognormal pulse model. The fraction of events that can be reliably ascertained to be temporally and spectrally similar to the exemplar, GRB 980425--possibly associated with SN 1998bw--is 4/1573 or 0.25%. This fraction could be as high as 8/1573 (0.5%) if the dimmest bursts are included. Approximately 1.5% of bursts are morphologically similar to GRB 980425 but have emission above ~300 keV. A search of supernova catalogs containing 630 detections during BATSE's lifetime reveals only one burst (GRB 980425) within a 3 month time window and within the total 3 σ BATSE error radius that could be associated with a Type Ib/c supernova. Thus, we find no further evidence to support a single-pulse GRB and SN Ib/c connection. We also find no tendency for any set of single-pulse GRBs to fall near the supergalactic plane, whereas SNe of Type Ib/c do show this tendency--evidence that the two phenomena are not related.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- June 1999
- DOI:
- 10.1086/307299
- arXiv:
- arXiv:astro-ph/9807322
- Bibcode:
- 1999ApJ...518..901N
- Keywords:
-
- GAMMA RAYS: BURSTS;
- METHODS: STATISTICAL;
- STARS: SUPERNOVAE: GENERAL;
- Gamma Rays: Bursts;
- Methods: Statistical;
- Stars: Supernovae: General;
- Astrophysics
- E-Print:
- 25 pages, 5 figures