相关论文: A Hot Spot Model for Black Hole QPOs

We have investigated the X-ray timing properties of XTE J1550-564 during 60 RXTE PCA observations made between 1998 September 18 and November 28. We detect quasi-periodic oscillations (QPOs) near 185 Hz during four time intervals. The QPO…

We apply the relativistic precession (RP) model with its variants and the resonance epicyclic model with its variants, based on the frequencies of the geodesic epicyclic motion in the field of a Kerr black hole, to put limits on the mass of…

An appearance or disappearance of QPOs associated with the variation of X-ray flux can be used to decipher the accretion ejection mechanism of black hole X-ray sources. We searched and studied such rapid transitions in H1743-322 using RXTE…

The connection of type-B QPOs to the hot flow in the inner accretion disk region is vaguely understood in black hole X-ray binaries. We performed spectral and timing studies of twenty-three observations where type-C and type-B QPOs with…

The remarkable discovery of kilohertz quasi-periodic brightness oscillations (QPOs) in the accretion-powered emission from some sixteen neutron-star low-mass X-ray binary systems has led to much speculation about and theoretical modeling of…

We report the detection of high frequency variability in the black hole X-ray transient XTE J1650-500. A quasi-periodic oscillation (QPO) was found at 250 Hz during a transition from the hard to the soft state. We also detected less…

We numerically investigate the effects of black hole spin and local dissipation profiles on high-frequency quasi-periodic oscillation (HFQPO) observed in black hole X-ray binaries (BHXB). Our HFQPO power spectra arise from self-consistent…

In this work, we probe the well known thermodynamic phase structure of black hole through the lens of its quasi-periodic oscillations (QPOs). Can QPOs be influenced by black hole phase transitions? Do they carry any signature of such…

In previous papers we proposed a model that high-frequency quasi-periodic oscillations (QPOs) observed in black-hole and neutron-star X-ray binaries are disk oscillations (inertial-acoustic and/or g-mode oscillations) resonantly excited on…

We compare our calculations of the frequencies of the fundamental g, c, and p--modes of relativistic thin accretion disks with recent observations of high frequency QPOs in X-ray binaries with black hole candidates. These classes of modes…

We compile observations of high-frequency quasi-periodic oscillations (QPOs) around black holes, both stellar and supermassive, and compare their positions in the parameter space of black hole mass, spin, and oscillation frequency. We find…

Quasi-periodic oscillations (QPOs) observed in the power spectrum of black holes are unique observational probes to the background spacetime since they can be directly related to the timescales associated with the motion of matter orbiting…

Low Mass X-ray Binaries (LMXBs) with either a black hole or a neutron star show power spectra characterised by Quasi Periodic Oscillations (QPOs). Twin peak high frequency QPOs are characterised by frequencies that are typical for matter…

In this work, we report for the first time two repeated quasi-periodic oscillations (QPOs) in the light curve of the Flat Spectrum Radio Quasar (FSRQ) S5 1044+71. This source was observed by the Transiting Exoplanet Survey Satellite (TESS)…

Recent X-ray timing and spectral observations of black hole binaries in outburst have redefined methods for investigating the properties of Galactic black holes and the physics of accretion flows. High-frequency X-ray QPOs in 5 systems…

We study energy dependencies of quasi-periodic oscillations from a number of black hole X-ray binaries. The selected sources were observed by RXTE at time periods close to state transitions and showed QPO in the 1-10 Hz range. We have…

Two inter-related peaks occur in high-frequency power spectra of X-ray lightcurves of several black-hole candidates. We further explore the idea that a non-linear resonance mechanism, operating in strong-gravity regime, is responsible for…

Black holes in dense astrophysical environments, such as globular clusters or in the vicinity of other massive objects, may possess accelerations. Such acceleration would modulate the characteristics of the quasi-periodic oscillations…

We numerically examine centrifugally supported shock waves in 2D rotating accretion flows around a stellar-mass (10M_sun) and a supermassive (10^6M_sun) black holes over a wide range of input accretion rates of 10^7 >\dot M/\dot…

Twin peak high frequency quasi-periodic oscillations (HF QPOs) observed in the power spectra of Low Mass X-ray Binaries (LMXBs), with either a black hole or a neutron star, have central frequencies that are typical of the orbital motion…