Related papers: For whom the disc tolls
The study of quasi-periodic oscillations (QPOs) of X-ray flux observed in many microquasars can provide a powerful tool for testing of the phenomena occurring in strong gravity regime. QPOs phenomena can be well related to the oscillations…
Quasi-Periodic Oscillations (QPOs) observed in the X-ray flux emitted by accreting black holes, are associated to phenomena occurring near the horizon. Future very large area X-ray instruments will be able to measure QPO frequencies with…
The paper considers the possibility of the existence of the axial current, that is directed along the axis of rotation and arises due to the presence of the Q-ball.
Astronomy is presently experiencing profound growth in the deployment of machine learning to explore large datasets. However, transient quasi-periodic oscillations (QPOs) which appear in power density spectra of many X-ray binary system…
We have proposed in previous papers that the high-frequency pair QPOs observed in black-hole binaries with frequency ratio 3:2 are inertial-acoustic oscillations (nearly horizontal oscillations with no node in the vertical direction) or…
Type-C quasi-periodic oscillations (QPOs) are the low-frequency QPOs most commonly observed during the hard spectral state of X-ray binary systems. The leading model for these QPOs is the Lense-Thirring precession of a hot, geometrically…
Given the peculiar and (in spite of many efforts) unexplained quasi-periodic oscillation (QPO) twin peak phenomena in accretion disc PSD observations, the present exploratory analytical article tries to inquire deeper into the relationship…
The results on polarized parton densities (PDFs) obtained using different methods of QCD analysis of the present polarized DIS data are discussed. Their dependence on the method used in the analysis, accounting or not for the kinematic and…
There is strong evidence that the observed kHz Quasi Periodic Oscillations (QPOs) in the X-ray flux of neutron star and black hole sources in LMXRBs are linked to Einstein's General Relativity. Abramowicz&Klu\'zniak (2001) suggested a…
We report the discovery of a new quasi-period oscillation (QPO) at 0.22 Hz, centered on the source spin frequency of the high mass X-ray binary system V~0332+53 when the source was observed during its November 2004/March 2005 outburst by…
We utilize the Monte Carlo radiation transport code, Pandurata, to create images, spectra, polarization maps, and light curves from a set of general relativistic magnetohydrodynamic simulations of tilted, truncated, black hole accretion…
Low-frequency quasi-periodic oscillations (QPOs) are commonly observed in black hole X-ray binaries, and their frequency has been found to correlate with various spectral properties. In this work, we present a detailed timing analysis of…
We consider the situation where a spin-induced wavy perturbation is present on disks of neutron-star low-mass X-ray binaries. By non-linearly coupling with the perturbation, some modes of disk oscillations resonantly interact with the…
The Bardeen-Petterson effect around a rapidly-rotating compact object causes a tilted accretion disk to warp into the equatorial plane of the rotating body. Viscous forces cause the accretion flow to divide into two distinct regions - an…
Quasi-periodic oscillation (QPO) detected in the X-ray radiation of black hole X-ray binaries (BHXBs) is thought to originate from dynamical processes in the close vicinity of the black holes (BHs), and thus carries important physical…
We present the results of the analysis of a large database of X-ray observations of 22 galactic black-hole transients with the Rossi X-Ray timing explorer throughout its operative life for a total exposure time of ~12 Ms. We excluded…
I comment on some theoretical work presented at QCD Moriond 2006.
We have studied the dependence of the high frequency Quasi-periodic Oscillation (QPO) (~284 Hz) on the phase of the low frequency QPO (~6 Hz) in the black hole X-ray binary XTE J1550-564 in the observations of the Rossi X-ray Timing…
The high time resolution and large area of the Rossi X-ray Timing Explorer have been essential in the detection and characterization of high-frequency quasi-periodic variability in the flux from neutron stars in low-mass X-ray binaries. An…
In this work, we examine the influence of nonlinear electrodynamics (NED) and $f(R,T)$ gravity on quasi-periodic oscillations (QPOs) around a magnetically charged black hole. By analyzing the effective potential, specific energy, and…