X-ray spectral and flux variability of the microquasar GRS 1758-258 on timescales from weeks to years

Hirsch, Maria; Pottschmidt, Katja; Smith, David M.; Bodaghee, Arash; Cadolle Bel, Marion; Grinberg, Victoria; Hell, Natalie; Krauß, Felicia; Kreykenbohm, Ingo; Lohfink, Anne; Nowak, Michael A.; Rodrigues, Bárbara H.; Soria, Roberto; Tomsick, John A.; Wilms, Jörn

doi:10.1051/0004-6361/201834647

Title: X-ray spectral and flux variability of the microquasar GRS 1758-258 on timescales from weeks to years

Journal Article · Fri Apr 17 00:00:00 EDT 2020 · Astronomy and Astrophysics

DOI:https://doi.org/10.1051/0004-6361/201834647· OSTI ID:1638438

Hirsch, Maria ^[1];

^[2]; Smith, David M. ^[3];

^[4]; Cadolle Bel, Marion ^[5];

^[6];

^[7];

^[8];

^[1]; Lohfink, Anne ^[9];

^[10]; Rodrigues, Bárbara H. ^[11];

^[12];

^[13];

^[1]

Univ. Erlangen-Nürnberg, Bamberg (Germany)
NASA Goddard Space Flight Center (GSFC), Greenbelt, MD (United States); Univ. of Maryland Baltimore County (UMBC), Baltimore, MD (United States)
Univ. of California, Santa Cruz, CA (United States)
Georgia College and State Univ., Milledgeville, GA (United States)
Max Planck Computing and Data Facility (Garching)
Univ. Tubingen (Germany)
Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
Univ. of Amsterdam (Netherlands); Pennsylvania State Univ., University Park, PA (United States)
Montana State Univ., Bozeman, MT (United States)
Washington Univ., St. Louis, MO (United States)
Instituto Nacional de Pesquisas Espaciais, San Jose dos Campos (Brazil)
Chinese Academy of Sciences (CAS), Beijing (China); Univ. of Sydney, NSW (Australia)
Univ. of California, Berkeley, CA (United States)

We present the spectral and timing evolution of the persistent black hole X-ray binary GRS 1758-258 based on almost 12 years of observations using the Rossi X-ray Timing Explorer Proportional Counter Array. While the source was predominantly found in the hard state during this time, it entered the thermally dominated soft state seven times. In the soft state GRS 1758-258 shows a strong decline in flux above 3 keV rather than the pivoting flux around 10 keV more commonly shown by black hole transients. In its 3–20 keV hardness intensity diagram, GRS 1758-258 shows a hysteresis of hard and soft state fluxes typical for transient sources in outburst. The RXTE-PCA and RXTE-ASM long-term light curves do not show any orbital modulations in the range of 2–30 d. However, in the dynamic power spectra significant peaks drift between 18.47 and 18.04 d for the PCA data, while less significant signatures between 19 d and 20 d are seen for the ASM data as well as for the Swift/BAT data. We discuss different models for the hysteresis behavior during state transitions as well as possibilities for the origin of the long term variation in the context of a warped accretion disk.

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Research Organization:: Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

Sponsoring Organization:: USDOE National Nuclear Security Administration (NNSA)

Grant/Contract Number:: AC52-07NA27344

OSTI ID:: 1638438

Report Number(s):: LLNL-JRNL-761006; 1432-0746; 949967; TRN: US2201779

Journal Information:: Astronomy and Astrophysics, Vol. 636; ISSN 0004-6361

Publisher:: EDP SciencesCopyright Statement

Country of Publication:: United States

Language:: English

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Cited by: 2 works

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