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arXiv · 2203.05308

The evolution of the corona in MAXI J1535-571 through type-C quasi-periodic oscillations with Insight-HXMT

Yuexin Zhang·Mariano Méndez·Federico García·Shuang-Nan Zhang·Konstantinos Karpouzas·Diego Altamirano·Tomaso M. Belloni·Jinlu Qu·Shu Zhang·Lian Tao·Liang Zhang·Yue Huang·Lingda Kong·Ruican Ma·Wei Yu·Divya Rawat·Candela Bellavita
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Abstract

Type-C quasi-periodic oscillations (QPOs) in black hole X-ray transients can appear when the source is in the low-hard and hard-intermediate states. The spectral-timing evolution of the type-C QPO in MAXI J1535-571 has been recently studied with Insight-HXMT. Here we fit simultaneously the time-averaged energy spectrum, using a relativistic reflection model, and the fractional rms and phase-lag spectra of the type-C QPOs, using a recently developed time-dependent Comptonization model when the source was in the intermediate state. We show, for the first time, that the time-dependent Comptonization model can successfully explain the X-ray data up to 100 keV. We find that in the hard-intermediate state the frequency of the type-C QPO decreases from 2.6 Hz to 2.1 Hz, then increases to 3.3 Hz, and finally increases to ~ 9 Hz. Simultaneously with this, the evolution of corona size and the feedback fraction (the fraction of photons up-scattered in the corona that return to the disc) indicates the change of the morphology of the corona. Comparing with contemporaneous radio observations, this evolution suggests a possible connection between the corona and the jet when the system is in the hard-intermediate state and about to transit into the soft-intermediate state.

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Yuexin Zhang, Mariano Méndez, Federico García, Shuang-Nan Zhang, Konstantinos Karpouzas, Diego Altamirano, Tomaso M. Belloni, Jinlu Qu, Shu Zhang, Lian Tao, Liang Zhang, Yue Huang, Lingda Kong, Ruican Ma, Wei Yu, Divya Rawat, Candela Bellavita. 2022-03-10. The evolution of the corona in MAXI J1535-571 through type-C quasi-periodic oscillations with Insight-HXMT. https://doi.org/10.1093/mnras%2Fstac690

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