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Near-Infrared and X-Ray Observations of the Enigmatic G70.7+1.2

Cameron, P. B. and Kulkarni, S. R. (2007) Near-Infrared and X-Ray Observations of the Enigmatic G70.7+1.2. Astrophysical Journal Letters, 665 (2). L135-L138. ISSN 2041-8205. doi:10.1086/521077.

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We present high-resolution imaging of the puzzling radio and optical nebula G70.7+1.2 with the Keck Observatory's laser guide star adaptive optics (LGS-AO) system and the Chandra X-Ray Observatory. The archival X-ray observations show a hard (Γ ≈ 1.8), low-luminosity (L_X ≈ 4 × 10^(31) ergs s^(-1)) point source at the center of the nebula. Follow-up LGS-AO near-infrared imaging of the Chandra error circle reveals a relatively bright (K' ≈ 14 mag) counterpart. Both its color and brightness are consistent with a heavily obscured B star or possibly a late G/early K giant. The most plausible explanation is that this newly discovered X-ray source is a nonaccreting B star/pulsar binary powering the radio and optical nebula. If so, the luminous Be star discussed in the literature seemingly embedded in the nebula is not the dominant force responsible for shaping G70.7+1.2. Thus, we suggest that G70.7+1.2 is the result of two unrelated objects (a B star X-ray binary and a Be star) interacting with a dense molecular cloud. With this explanation we believe we have solved the mystery of the origin of G70.7+1.2.

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Kulkarni, S. R.0000-0001-5390-8563
Additional Information:© 2007 The American Astronomical Society. Received 2006 August 22; accepted 2007 June 22; published 2007 August 6. We thank A. Kraus for useful discussions and the anonymous referee for helpful comments. This work is supported in part by grants from the National Science Foundation and NASA. The W. M. Keck Observatory is operated as a scientific partnership among the California Institute of Technology, the University of California, and the National Aeronautics and Space Administration. The Observatory was made possible by the generous financial support of the W. M. Keck Foundation.
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W. M. Keck FoundationUNSPECIFIED
Subject Keywords:ISM : individual (G70.7+1.2); X-rays : binaries
Issue or Number:2
Record Number:CaltechAUTHORS:20091027-095344776
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Official Citation:Near-Infrared and X-Ray Observations of the Enigmatic G70.7+1.2 P. B. Cameron and S. R. Kulkarni 2007 ApJ 665 L135-L138 doi: 10.1086/521077
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:16488
Deposited By: Tony Diaz
Deposited On:29 Oct 2009 21:03
Last Modified:08 Nov 2021 23:27

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