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Long-Wavelength Excesses in Two Highly Obscured High-Mass X-Ray Binaries: IGR J16318–4848 and GX 301–2

Kaplan, D. L. and Moon, D.-S. and Reach, W. T. (2006) Long-Wavelength Excesses in Two Highly Obscured High-Mass X-Ray Binaries: IGR J16318–4848 and GX 301–2. Astrophysical Journal Letters, 649 (2). L107-L110. ISSN 2041-8205.

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We present evidence for excess long-wavelength emission from two high-mass X-ray binaries, IGR J16318-4848 and GX 301-2, that show enormous obscuration (N_H ≃ 10^(23)-10^(24) cm^(-2)) in their X-ray spectra. Using archival near- and mid-infrared data, we show that the spectral energy distributions of IGR J16318-4848 and GX 301-2 are substantially higher in the mid-infrared than their expected stellar emission. We successfully fit the excesses with ~1000 K blackbodies, which suggests that they are due to warm circumstellar dust that also gives rise to the X-ray absorption. However, we need further observations to constrain the detailed properties of the excesses. This discovery highlights the importance of mid-infrared observations for understanding highly obscured X-ray binaries.

Item Type:Article
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URLURL TypeDescription
Kaplan, D. L.0000-0001-6295-2881
Moon, D.-S.0000-0003-4200-5064
Reach, W. T.0000-0001-8362-4094
Additional Information:© 2006 American Astronomical Society. Received 2006 June 15; accepted 2006 August 14; published 2006 September 13. We thank an anonymous referee for comments that helped improve and clarify this paper. We also thank D. Chakrabarty and M. van Kerkwijk for help and advice. This work is based in part on archival data obtained with the Spitzer Space Telescope, which is operated by the JPL, Caltech, under NASA contract 1407. Support for this work was provided by NASA through an award issued by JPL/Caltech. This research has also made use of the data products from the Two Micron All Sky Survey, which is a joint project of the University of Massachusetts and the Infrared Processing and Analysis Center/Caltech, funded by NASA and NSF. D. S. M. was supported by a Millikan fellowship from Caltech; D. L. K. was supported in part by a fellowship from the Fannie and John Hertz Foundation. Facilities: Spitzer(IRAC), MSX
Funding AgencyGrant Number
Robert A. Millikan FellowshipUNSPECIFIED
Fannie and John Hertz FoundationUNSPECIFIED
Subject Keywords:circumstellar matter; infrared: stars; stars: emission-line, Be; X-rays: binaries; X-rays: individual (GX 301–2, IGR J16318–4848)
Issue or Number:2
Record Number:CaltechAUTHORS:20110630-132516557
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Official Citation:Long-Wavelength Excesses in Two Highly Obscured High-Mass X-Ray Binaries: IGR J16318–4848 and GX 301–2 D. L. Kaplan, D.-S. Moon, and W. T. Reach doi: 10.1086/508369
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:24281
Deposited By: Ruth Sustaita
Deposited On:30 Jun 2011 20:40
Last Modified:19 Nov 2019 00:48

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