A VARIABLE NEAR-INFRARED COUNTERPART TO THE NEUTRON-STAR LOW-MASS X-RAY BINARY 4U 1705 – 440
Author(s)
Homan, Jeroen; Kaplan, David L.; van den Berg, Maureen; Young, Andrew J.
DownloadHoman-2009-A VARIABLE NEAR-INFR.pdf (703.8Kb)
PUBLISHER_POLICY
Publisher Policy
Article is made available in accordance with the publisher's policy and may be subject to US copyright law. Please refer to the publisher's site for terms of use.
Terms of use
Metadata
Show full item recordAbstract
We report the discovery of a near-infrared (NIR) counterpart to the persistent neutron-star low-mass X-ray binary 4U 1705 – 440, at a location consistent with its recently determined Chandra X-ray position. The NIR source is highly variable, with Ks -band magnitudes varying between 15.2 and 17.3 and additional J- and H-band observations revealing color variations. A comparison with contemporaneous X-ray monitoring observations shows that the NIR brightness correlates well with X-ray flux and X-ray spectral state. We also find possible indications of a change in the slope of the NIR/X-ray flux relation among different X-ray states. We discuss and test various proposed mechanisms for the NIR emission from neutron-star low-mass X-ray binaries and conclude that the NIR emission in 4U 1705 – 440 is most likely dominated by X-ray heating of the outer accretion disk and the secondary star.
Date issued
2009-02Department
MIT Kavli Institute for Astrophysics and Space ResearchJournal
Astrophysical Journal
Publisher
Institute of Physics/American Astronomical Society
Citation
Homan, Jeroen, David L. Kaplan, Maureen van den Berg, and Andrew J. Young. “A VARIABLE NEAR-INFRARED COUNTERPART TO THE NEUTRON-STAR LOW-MASS X-RAY BINARY 4U 1705 – 440.” The Astrophysical Journal 692, no. 1 (February 10, 2009): 73–80. © 2009 American Astronomical Society.
Version: Final published version
ISSN
0004-637X
1538-4357