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arXiv · 2012.01825

Testing evolution of LFQPOs with mass accretion rate in GRS 1915+105 with Insight-HXMT

Honghui Liu·Long Ji·Cosimo Bambi·Pankaj Jain·Ranjeev Misra·Divya Rawat·J. S. Yadav·Yuexin Zhang
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Abstract

Using the Insight-HXMT observations of GRS 1915+105 when it exhibits low frequency quasi-periodic oscillations (QPOs), we measure the evolution of the QPO frequency along with disk inner radius and mass accretion rate. We find a tight positive correlation between the QPO frequency and mass accretion rate. Our results extend the finding of previous work with AstroSat to a larger range of accretion rate with independent instruments and observations. Treating the QPO frequency of GRS 1915+105 as the relativistic dynamic frequency of a truncated disk, we are able to confirm the high spin nature of the black hole in GRS 1915+105. We also address the potential of our finding to test general relativity in the future.

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Honghui Liu, Long Ji, Cosimo Bambi, Pankaj Jain, Ranjeev Misra, Divya Rawat, J. S. Yadav, Yuexin Zhang. 2021-03-09. Testing evolution of LFQPOs with mass accretion rate in GRS 1915+105 with Insight-HXMT. https://doi.org/10.3847/1538-4357%2Fabdf65

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