Evidence of Class Transitions in GRS 1915+105 from IXAE Data

Sandip K. Chakrabarti; A. Nandi; Asit Choudhury; Utpal Chatterjee

doi:10.1086/383235

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Evidence of Class Transitions in GRS 1915+105 from IXAE Data

Sandip K. Chakrabarti·A. Nandi·Asit Choudhury·Utpal Chatterjee

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Abstract

GRS 1915+105 shows at least twelve distinct classes of light curves. By analysing the data obtained from Indian X-ray Astronomy Experiment (IXAE) instrument aboard IRS-P3 satellite, we show that in at least two days, transitions between one class to another were observed. In these days the so-called $κ$ class went to $ρ$ class and $χ$ class went to $ρ$ class. In the frequency-time plane such transitions exhibited change in quasi-periodic oscillation (QPO) frequency. We could detect that low-frequency QPOs can occur in anticipation of a class transition several hundred minutes before the actual transition

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Sandip K. Chakrabarti, A. Nandi, Asit Choudhury, Utpal Chatterjee. 2005-01-14. Evidence of Class Transitions in GRS 1915+105 from IXAE Data. https://doi.org/10.1086/383235

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