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Swift observations of 1FGL J1018.6-5856

An, Hongjun and Dufour, François and Kaspi, Victoria M. and Harrison, Fiona A. (2013) Swift observations of 1FGL J1018.6-5856. Astrophysical Journal, 775 (2). Art. No. 135. ISSN 0004-637X.

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We report on X-ray properties of the gamma-ray binary 1FGL J1018.6–5856 using observations obtained with the Swift X-ray telescope. Using 54 observations made between MJD 55575 and 55984, we find that the X-ray flux is modulated at a period of 16.57 ± 0.11 days, which is consistent with previous reports based on gamma-ray data. We find that the X-ray maximum at phase 0 previously reported may not be a persistent feature of the source: the dramatic increases at phase 0 were only detected for ~100 days and were not detected thereafter. Rather, the persistent sinusoidal maximum seems to be at phase 0.3-0.4, and is misaligned with the gamma-ray (GeV) peak. We also find evidence that the source's X-ray flux is correlated with the spectral hardness in the 0.5-10 keV band. Such a correlation has also been reported in the gamma-ray binaries LS 5039 and LS I +61°303 and can help us to understand the X-ray emission mechanisms of the sources.

Item Type:Article
Related URLs:
URLURL TypeDescription Paper
Kaspi, Victoria M.0000-0001-9345-0307
Harrison, Fiona A.0000-0003-2992-8024
Additional Information:© 2013 American Astronomical Society. Received 2013 May 28; accepted 2013 August 7; published 2013 September 16. This research has made use of data obtained from the High Energy Astrophysics Science Archive Research Center (HEASARC), provided by NASA’s Goddard Space Flight Center. V.M.K. acknowledges support from an NSERC Discovery Grant, the FQRNT Centre de Recherche Astrophysique du Québec, an R. Howard Webster Foundation Fellowship from the Canadian Institute for Advanced Research (CIFAR), the Canada Research Chairs Program, and the Lorne Trottier Chair in Astrophysics and Cosmology.
Funding AgencyGrant Number
Natural Sciences and Engineering Research Council of Canada (NSERC)UNSPECIFIED
Fonds de recherche du Québec – Nature et technologies (FRQNT)UNSPECIFIED
Canadian Institute for Advanced Research (CIFAR)UNSPECIFIED
Canada Research Chairs ProgramUNSPECIFIED
Lorne Trottier Chair in Astrophysics and CosmologyUNSPECIFIED
Subject Keywords: binaries: close; gamma rays: stars; stars: individual (1FGL J1018.6–5856); X-rays: binaries
Issue or Number:2
Record Number:CaltechAUTHORS:20131025-104109906
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Official Citation:Swift Observations of 1FGL J1018.6–5856 Hongjun An et al. 2013 ApJ 775 135
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:42065
Deposited By: Ruth Sustaita
Deposited On:25 Oct 2013 18:20
Last Modified:04 Dec 2019 20:24

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