Knust, F, Greiner, J, van Eerten, HJ, Schady, P, Kann, DA, Chen, T-W, Delvaux, C, Graham, JF, Klose, S, Kruehler, T, McConnell, NJ, Guelbenzu, AN, Perley, DA, Schmidl, S, Schweyer, T, Tanga, M and Varela, K (2017) Long optical plateau in the afterglow of the short GRB 150424A with extended emission. Astronomy & Astrophysics, 607. ISSN 1432-0746
|
Text
Knust_2017_AA_607_84.pdf - Published Version Download (486kB) | Preview |
Abstract
Context. Short-duration gamma-ray bursts (GRBs) with extended emission form a subclass of short GRBs, comprising about 15% of the short-duration sample. Afterglow detections of short GRBs are also rare (about 30%) because of their lower luminosity.
Aims. We present a multiband data set of the short burst with extended emission, GRB 150424A, comprising of GROND observations, complemented with data from Swift/UVOT, Swift/XRT, HST, Keck/LRIS, and data points from the literature. The GRB 150424A afterglow shows an extended plateau phase, lasting about 8 h. The analysis of this unique GRB afterglow might shed light on the understanding of afterglow plateau emission, the nature of which is still under debate.
Methods. We present a phenomenological analysis made by applying fireball closure relations and interpret the findings in the context of the fireball model. We discuss the plausibility of a magnetar as a central engine, which would be responsible for additional and prolonged energy injection into the fireball.
Results. We find convincing evidence for energy injection into the afterglow of GRB 150424A. We find that a magnetar spin-down as the source for a prolonged energy injection requires that at least 4% of the spin-down energy is converted into radiation.
Item Type: | Article |
---|---|
Uncontrolled Keywords: | 0201 Astronomical And Space Sciences |
Subjects: | Q Science > QB Astronomy Q Science > QC Physics |
Divisions: | Astrophysics Research Institute |
Publisher: | EDP Sciences |
Related URLs: | |
Date Deposited: | 21 Feb 2018 12:09 |
Last Modified: | 04 Sep 2021 03:07 |
DOI or ID number: | 10.1051/0004-6361/201730578 |
URI: | https://researchonline.ljmu.ac.uk/id/eprint/8095 |
View Item |