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arXiv · 1003.0477

The hard state of black hole candidates: XTE J1752-223

T. Muñoz-Darias·S. Motta·D. Pawar·T. M. Belloni·S. Campana·D. Bhattacharya
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Abstract

We present a two-day long RXTE observation and simultaneous Swift data of the bright X-ray transient XTE J1752-223. Spectral and timing properties were stable during the observation. The energy spectrum is well described by a broken power-law with a high energy cut-off. A cold disc (~ 0.3 keV) is observed when Swift/XRT data are considered. The fractional rms amplitude of the aperiodic variability (0.002-128 Hz) is 48.2 +- 0.1% and it is not energy dependent. The continuum of the power density spectrum can be fitted by using four broad-band Lorentzians. A high frequency (~ 21 Hz) component and two weak QPO-like features are also present. Time-lags between soft and hard X-rays roughly follow the relation time-lag~vnu^ {-0.7}, with delays dropping from ~ 0.5 (0.003 Hz) to ~ 0.0015 (>10 Hz) seconds. Our results are consistent with XTE J1752-223 being a black-hole candidate, with all timing and spectral components very similar to those of Cyg X-1 during its canonical hard state.

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T. Muñoz-Darias, S. Motta, D. Pawar, T. M. Belloni, S. Campana, D. Bhattacharya. 2010-03-01. The hard state of black hole candidates: XTE J1752-223. https://doi.org/10.1111/j.1745-3933.2010.00842.x

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