NuSTAR and XMM-Newton observations of 1E1743.1-2843: indications of a neutron star LMXB nature of the compact object
Creators
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1.
National Institute for Astrophysics
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2.
Columbia University
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3.
Massachusetts Institute of Technology
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4.
University of California, Berkeley
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5.
Technical University of Denmark
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California Institute of Technology
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Harvard-Smithsonian Center for Astrophysics
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Space Research Institute
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9.
Harvard University
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10.
European Southern Observatory
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11.
Jet Propulsion Lab
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12.
Goddard Space Flight Center
Abstract
We report on the results of NuSTAR and XMM-Newton observations of the persistent X-ray source 1E1743.1-2843, located in the Galactic Center region. The source was observed between 2012 September and October by NuSTAR and XMM-Newton, providing almost simultaneous observations in the hard and soft X-ray bands. The high X-ray luminosity points to the presence of an accreting compact object. We analyze the possibilities of this accreting compact object being either a neutron star (NS) or a black hole, and conclude that the joint XMM-Newton and NuSTAR spectrum from 0.3 to 40 keV fits a blackbody spectrum with kT ~ 1.8 keV emitted from a hot spot or an equatorial strip on an NS surface. This spectrum is thermally Comptonized by electrons with kT_e ~ 4.6 keV. Accepting this NS hypothesis, we probe the low-mass X-ray binary (LMXB) or high-mass X-ray binary (HMXB) nature of the source. While the lack of Type-I bursts can be explained in the LMXB scenario, the absence of pulsations in the 2 mHz–49 Hz frequency range, the lack of eclipses and of an IR companion, and the lack of a K_ɑline from neutral or moderately ionized iron strongly disfavor interpreting this source as a HMXB. We therefore conclude that 1E1743.1-2843 is most likely an NS-LMXB located beyond the Galactic Center. There is weak statistical evidence for a soft X-ray excess which may indicate thermal emission from an accretion disk. However, the disk normalization remains unconstrained due to the high hydrogen column density (N_H ~ 1.6 x 10^(23)cm^(-2).
Additional Information
© 2016 The American Astronomical Society. Received 2015 October 16; accepted 2016 March 4; published 2016 May 5. This work was supported under NASA Contract No. NNG08FD60C, and made use of data from the NuSTAR mission, a project led by the California Institute of Technology, managed by the Jet Propulsion Laboratory, and funded by the National Aeronautics and Space Administration. We thank the NuSTAR Operations, Software and Calibration teams for support with the execution and analysis of these observations. This research has made use of the NuSTAR Data Analysis Software (NuSTARDAS) jointly developed by the ASI Science Data Center (ASDC, Italy) and the California Institute of Technology (USA). The Italian authors acknowledge the Italian Space Agency (ASI) for financial support by ASI/INAF grant I/037/12/0. RK acknowledges support from Russian Science Foundation (grant 14-22-00271).Attached Files
Published - apj_822_1_57.pdf
Submitted - 1603.02016v2.pdf
Files
1603.02016v2.pdf
Additional details
Identifiers
- Eprint ID
- 65481
- Resolver ID
- CaltechAUTHORS:20160318-104326136
Related works
- Describes
- http://arxiv.org/abs/1603.02016 (URL)
Funding
- NASA
- NNG08FD60C
- NASA/JPL/Caltech
- Agenzia Spaziale Italiana (ASI)
- I/037/12/0
- Istituto Nazionale di Astrofisica (INAF)
- Russian Science Foundation
- 14-22-00271
Dates
- Created
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2016-03-18Created from EPrint's datestamp field
- Updated
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2021-11-10Created from EPrint's last_modified field
Caltech Custom Metadata
- Caltech groups
- NuSTAR
- Other Numbering System Name
- Space Radiation Laboratory
- Other Numbering System Identifier
- 2016-55