Alternating lags of QPO harmonics : A Generic model and its application to the 67 millihertz QPO of GRS 1915+105

Abstract

A generic model for alternating lags in QPO harmonics is presented where variations in the photon spectrum are caused by oscillations in two parameters that characterize the spectrum. It is further assumed that variations in one of the parameters is linearly driven by variations in the other after a time delay $t_d$. It is shown that alternating lags will be observed for a range of $t_d$ values. A phenomenological model based on this generic one is developed which can explain the amplitude and phase lag variation with energy of the fundamental and the next three harmonics of the 67 mHz QPO observed in GRS 1915+105. The phenomenological model also predicts the variation of the Bicoherence phase with energy, which can be checked by further analysis of the observational data.

5 pages, 3 figures, Accepted for publication in Astrophysical Journal

References in corpus (3)

• X-ray Properties of Black-Hole Binaries
• Two Years of INTEGRAL monitoring of GRS 1915+105 Part 2: X-Ray Spectro-Temporal Analysis
• The biphase explained: understanding the asymmetries in coupled Fourier components of astronomical timeseries

Cited by in corpus (13)

• A two-component Comptonisation model for the type-B QPO in MAXI J1348-630
• Phase-resolved spectroscopy of low frequency quasi-periodic oscillations in GRS 1915+105
• Time lags of the type-B QPO in MAXI J1348-630
• Multi-timescale X-ray reverberation mapping of accreting black holes
• Energy Dependent Time Delays of kHz Oscillations due to Thermal Comptonization
• The evolving properties of the corona of GRS 1915+105: A spectral-timing perspective through variable-Comptonisation modelling
• Variability and phase lags of the type-C quasi-periodic oscillation of MAXI J1348-630 with NICER
• On the energy dependence of the QPO phenomenon in the black hole system MAXI J1535-571
• Identifying the radiative components responsible for Quasi-Periodic Oscillations of black hole systems
• A model for the energy-dependent time-lag and rms of the heartbeat oscillations in GRS 1915+105
• A broadband spectral-timing study of QPOs in the bright black hole X-ray binary Swift J1727.8-1613
• A timing view of the heartbeat state of GRS 1915+105
• Detection of QPO Soft Lag during Outburst of Swift J1727.8-1613: Estimation of Instrinsic Parameters from Spectral Study