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GRB 070201: A possible soft gamma-ray repeater in M31

Ofek, E. O. and Muno, M. and Quimby, R. and Kulkarni, S. R. and Stiele, H. and Pietsch, W. and Nakar, E. and Gal-Yam, A. and Rau, A. and Cameron, P. B. and Cenko, S. B. and Kasliwal, M. M. and Fox, D. B. and Chandra, P. and Kong, A. K. H. and Barnard, R. (2008) GRB 070201: A possible soft gamma-ray repeater in M31. Astrophysical Journal, 681 (2). pp. 1464-1469. ISSN 0004-637X. doi:10.1086/587686.

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GRB 070201 was a bright, short-duration, hard-spectrum gamma-ray burst detected by the Interplanetary Network. Its error quadrilateral, which has an area of 0.124 deg^2, intersects some prominent spiral arms of the nearby M31 (Andromeda) galaxy. Given the properties of this GRB, along with the fact that LIGO data argue against a compact binary merger origin in M31, it is an excellent candidate to have been an extragalactic soft gamma-ray repeater (SGR) giant flare, with an energy of 1.4 × 10^45 ergs. However, we cannot rule out the possibility that it was a short-duration GRB in the background. Analysis of ROTSE-IIIb visible-light observations of M31, taken 10.6 hr after the burst and covering 42% of the GRB error region, does not reveal any optical transient down to a limiting magnitude of 17.1. We inspected archival and proprietary XMM-Newton X-ray observations of the intersection of the GRB error region and M31, obtained about 4 weeks prior to the outburst, in order to look for periodic variable X-ray sources. No SGR or anomalous X-ray pulsar (AXP) candidates (periods in the range 1-20 s) were detected. We discuss the possibility of detecting extragalactic SGRs/AXPs by identifying their periodic X-ray light curves. Our simulations suggest that the probability of detecting the periodic X-ray signal of one of the known Galactic SGRs/AXPs, if placed in M31, is about 10% using a 50 ks XMM-Newton exposure, increasing to 50% for a 2 Ms observation.

Item Type:Article
Related URLs:
URLURL TypeDescription
Ofek, E. O.0000-0002-6786-8774
Quimby, R.0000-0001-9171-5236
Kulkarni, S. R.0000-0001-5390-8563
Nakar, E.0000-0002-4534-7089
Gal-Yam, A.0000-0002-3653-5598
Rau, A.0000-0001-5990-6243
Cenko, S. B.0000-0003-1673-970X
Kasliwal, M. M.0000-0002-5619-4938
Fox, D. B.0000-0002-3714-672X
Kong, A. K. H.0000-0002-5105-344X
Additional Information:© 2008 The American Astronomical Society. Received 2007 December 13; accepted 2008 February 18. This work is supported in part by grants from NSF and NASA. H. S. acknowledges support from the Bundesministerium fur Wirtschaft und Technologie/Deutsches Zentrum fur Luft- und Raumfahrt (BMWI/DLR, FKZ 50 OR 0405). M. M. K. acknowledges the Moore Foundation for the George Ellory Hale Fellowship.
Funding AgencyGrant Number
Bundesministerium fur Wirtschaft und Technologie (BMWI)FKZ 50 OR 0405
Gordon and Betty Moore FoundationUNSPECIFIED
Deutsches Zentrum fur Luft- und Raumfahrt (DLR)UNSPECIFIED
Subject Keywords:galaxies: individual (M31); gamma rays: bursts; pulsars: general; stars: neutron; X-rays: individual (GRB 070201)
Issue or Number:2
Record Number:CaltechAUTHORS:20090505-092712678
Persistent URL:
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:14161
Deposited By: Tony Diaz
Deposited On:11 May 2009 21:36
Last Modified:08 Nov 2021 22:43

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