Reflection Spectroscopy of the Black Hole Binary XTE J1752-223 in Its Long-stable Hard State

Journal article

Publication Details

Author(s): Garcia JA, Steiner JF, Grinberg V, Dauser T, Connors RMT, Mcclintock JE, Remillard RA, Wilms J, Harrison FA, Tomsick JA
Journal: Astrophysical Journal
Publication year: 2018
Volume: 864
Journal issue: 1
ISSN: 0004-637X


We present a detailed spectral analysis of the black hole binary XTE J1752-223. in the hard state of its 2009 outburst. Regular monitoring of this source by the Rossi X-ray Timing Explorer mission provided high signal-to-noise spectra along the outburst rise and decay. During one full month this source stalled at similar to 30% of its peak count rate at a constant hardness and intensity. By combining all the data in this exceptionally stable hard state, we obtained an aggregate proportional counter array spectrum (3-45 keV) with 100. million counts, and a corresponding high energy X-ray timing experiment spectrum (20-140 keV) with 5.8. million counts. Implementing a version of our reflection code with a physical model for Comptonization, we obtain tight constraints on important physical parameters for this system. In particular, the inner accretion disk is measured very close in, at R-in =1.7 +/- 0.4 R-g. Assuming R-in = R-ISCO, we find a relatively high black hole spin (a* = 0.92 +/- 0.06). Imposing a lamppost geometry, we obtain a low inclination (i = 35 degrees +/- 4 degrees), which agrees with the upper limit found in the radio (i < 49 degrees). However, we note that this model cannot be statistically distinguished from a non-lamppost model with a free emissivity index, for which the inclination is markedly higher. Additionally, we find a relatively cool corona (57-70 keV) and large iron abundance (3.3-3.7 solar). We further find that properly accounting for Comptonization of the reflection emission improves the fit significantly and causes an otherwise low reflection fraction (similar to 0.2-0.3) to increase by an order of magnitude, in line with geometrical expectations for a lamppost corona. We compare these results with similar investigations reported for GX 339-4. in its bright hard state.

FAU Authors / FAU Editors

Dauser, Thomas Dr.
Dr.Karl-Remeis-Sternwarte Bamberg, Astronomisches Institut
Wilms, Jörn Prof. Dr.
Professur für Astronomie und Astrophysik

External institutions with authors

California Institute of Technology (Caltech)
European Space Research and Technology Centre (ESTEC, ESA)
Harvard University
Massachusetts Institute of Technology (MIT)
University of California, Berkeley

How to cite

Garcia, J.A., Steiner, J.F., Grinberg, V., Dauser, T., Connors, R.M.T., Mcclintock, J.E.,... Tomsick, J.A. (2018). Reflection Spectroscopy of the Black Hole Binary XTE J1752-223 in Its Long-stable Hard State. Astrophysical Journal, 864(1).

Garcia, Javier A., et al. "Reflection Spectroscopy of the Black Hole Binary XTE J1752-223 in Its Long-stable Hard State." Astrophysical Journal 864.1 (2018).


Last updated on 2019-30-04 at 02:08