Related papers: On the identification of substructure in phase-spa…
The investigation of the pulsation properties of pre-main-sequence intermediate-mass stars is a promising tool to evaluate the intrinsic properties of these stars and to constrain current evolutionary models. Many new candidates of this…
A near-equal mass binary black hole can clear a central cavity in a circumbinary accretion disk; however, previous works have revealed accretion streams entering this cavity. Here we use 2D hydrodynamical simulations to study the accretion…
The space-time correlations of streams of photons can provide fundamentally new channels of information about the Universe. Today's astronomical observations essentially measure certain amplitude coherence functions produced by a source.…
Determining the equation of state of matter at nuclear density and hence the structure of neutron stars has been a riddle for decades. We show how the imminent detection of gravitational waves from merging neutron star binaries can be used…
Accreting supermassive black hole binaries are powerful multimessenger sources emitting both gravitational and EM radiation. Understanding the accretion dynamics of these systems and predicting their distinctive EM signals is crucial to…
Autonomous orbit determination via integration of epoch-differenced gravity gradients and starlight refraction is proposed in this paper for low-Earth-orbiting satellites operating in GPS-denied environments. The starlight refrac-tion can…
Gravitational waves from the coalescence of compact objects carry information about their dynamics and the spacetime in regions where they are evolving. In particular, late-time tails and memory effects after the merger are two…
The detection of fast quasi-periodic variability from accreting black holes and neutron stars has been used to constrain their masses, radii, and spins. If the observed oscillations are linear modes in the accretion disks, then bounds can…
Accretion disks are three-dimensional, turbulent, often self-gravitating, magnetohydrodynamic flows, which can be modeled in detail with numerical simulations. In this paper, we present a new algorithm that is based on a spectral…
Ten years have passed since the global solutions of advective accretion disks around black holes and neutron stars were first discovered. Since then they are enjoying support from observers almost on a daily basis, more so in recent days…
Accretion onto compact objects is one of the most fundamental phenomena in the astrophysics, powering some of the most luminous objects in the sky. Along with this, accretion has also a key impact on the evolution of the Universe, through…
Stellar streams -- formed from tidally stripped globular clusters or dwarf galaxies -- are sensitive tracers of a galaxy's accretion history and gravitational potential. While numerous streams are known in the Milky Way (MW), the formation…
Context. One of the primary goals of Galactic Archaeology is to reconstruct the Milky Way's accretion history. To achieve this, significant efforts have been dedicated to identifying signatures of past accretion events. In particular, the…
We report on the numerical discovery of quasi-periodic oscillations (QPOs) associated with accretion through a non-axisymmetric magnetic boundary layer in the unstable regime, when two ordered equatorial streams form and rotate…
A general method is presented for estimating the uncertainty in hybrid models of gravitational waveforms from binary black-hole systems with arbitrary physical parameters, and thence the highest allowable initial orbital frequency for a…
Stellar companion of a black hole orbiting in an eccentric orbit will experience modulating tidal force with a periodicity same as that of the orbital period. This, in turn, would modulate accretion rates, and the seed photon flux which are…
Light propagation through turbulence produces speckles, whose ensemble behavior is typically characterized by snapshot intensity statistics. Here, we track the spatiotemporal evolution of individual speckles and quantify fragmentation,…
Radio astronomical observations have very poor signal to noise ratios, unlike in other disciplines. On the other hand, it is possible to observe the object of interest for long time intervals as well as using a wider bandwidth.…
(Context) In a Universe dominated by dark matter, halos are continuously accreting mass (violently or not) and such mechanism affects their dynamical state. (Aims) The evolution of dark matter halos in phase-space, and using the phase-space…
Resolved surveys of the Milky Way's stellar halo can obtain all 6 phase space coordinates of tens of thousands of individual stars, making it possible to compute their 3-dimensional orbits. Spectral analysis of large numbers of halo orbits…