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arXiv · 1905.08072

Long term variability of Swift J1753.5-0127]{Long term variability of Swift J1753.5-0127: X-ray spectral-temporal correlations during state transitions

Qingcui Bu·Lian Tao·Yu Lu·Shuangnan Zhang·Liang Zhang·Yue Huang·Li Chen·Jinlu Qu·Xiang Ma
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Abstract

We studied the long-term evolution of the spectral-temporal correlated properties of the black hole candidate Swift J1753.5-0127 from the onset of its outburst until 2011 with the Rossi X-ray Timing Explorer (RXTE). The source stayed most of its lifetime during hard state, with occasionally transitioned to the hard intermediate state. Similar to typical black hole transients, Swift J1753.5-0127 traces a clear hard line in absolute rms - intensity diagram during the low hard state, with expected highest absolute rms, while shows a clear turn during the hard intermediate state, accompanied by lower absolute rms. Different from Cyg X-1, we found that frequency-dependent time lag increased significantly in the 0.02 -- 3.2 Hz band during state transition in this source. The X-ray time lags in 0.02 -- 3.2 Hz can therefore be used as indicators of state transition in this source. Type-C QPO frequency is positively related with its fractional rms and X-ray photon index, suggesting a moving inwards disk/corona scenario. We discussed the physical interpretation of our results in our paper.

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Qingcui Bu, Lian Tao, Yu Lu, Shuangnan Zhang, Liang Zhang, Yue Huang, Li Chen, Jinlu Qu, Xiang Ma. 2019-05-20. Long term variability of Swift J1753.5-0127]{Long term variability of Swift J1753.5-0127: X-ray spectral-temporal correlations during state transitions. https://doi.org/10.1093/mnras/stz1400

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