Related papers: Gravitational-wave background from compact objects…
LISA will extend the search for gravitational waves (GWs) at $0.1\,{-}\,100$ mHz where loud signals from coalescing binary black holes of $ 10^4 \,{-}\,10^7\,\rm M_{\odot}$ are expected. Depending on their mass and luminosity distance, the…
Two-body gravitational interactions will occasionally lead to a stellar-mass compact object entering a very highly eccentric orbit around a massive black hole at the center of a galaxy. Gravitational radiation damping will subsequently…
Young star clusters are often born with such high stellar densities that stellar collisions play an important role in their further evolution. In such environments the same star may participate in several tens to hundreds of collisions…
Over the last few years X-ray observations of broad-line radio galaxies (BLRGs) by ASCA, RXTE and BeppoSAX have shown that these objects seem to exhibit weaker X-ray reflection features (such as the iron K\alpha line) than radio-quiet…
In this thesis we consider the data analysis problem of detecting gravitational waves emitted by inspiraling binary systems. Detection of gravitational waves will open a new window on the Universe enabling direct detection of systems such…
An overview is presented of possible cosmologically distant sources of gravitational wave backgrounds, especially those which might produce detectable backgrounds in the LISA band between 0.1 and 100 mHz. Examples considered here include…
After a short review of prominent properties of gravitational waves and the newly born gravitational astronomy, we focus on theoretical aspects. Analytic approximation methods in general relativity have played a crucial role in the recent…
A plethora of gravitational wave stochastic backgrounds populate the sensitivity window of the Laser Interferometer Space Antenna. We show that LISA can detect the anisotropy of the background corresponding to the multipole moments of order…
Massive stars may form in or be captured into AGN disks. Recent 1D studies employing stellar-evolution codes have demonstrated the potential for rapid growth of such stars through accretion up to a few hundred $M_\odot$. We perform 3D…
Over the next decade, third-generation interferometers and the space-based LISA mission will observe binaries in galactic centers involving supermassive black holes with millions of solar masses. More precise measurements of more extreme…
We consider gravitational waves emitted by various populations of compact binaries at cosmological distances. We use population synthesis models to characterize the properties of double neutron stars, double black holes and double white…
The detection of a gravitational capture of a stellar-mass compact object by a massive black hole (MBH) will allow us to test gravity in the strong regime. These sources form via two-body relaxation, by exchanging energy and angular…
The gravitational wave sky is expected to have isolated bright sources superimposed on a diffuse gravitational wave background. The background radiation has two components: a confusion limited background from unresolved astrophysical…
The disks of Active Galactic Nuclei (AGNs) have emerged as rich environments for the production and capture of stars and the compact objects that they leave behind. These stars produce long Gamma-Ray Bursts (LGRBs) at their deaths, while…
Detection of gravitational waves from accreting neutron stars (NSs) in our galaxy, due to ellipticity or internal oscillation, would be a breakthrough in our understanding of compact objects and explain the absence of NSs rotating near the…
Globular clusters house a population of compact binaries that will be interesting gravitational wave sources for LISA. We provide estimates for the numbers of sources of several categories and discuss the sensitivity of LISA to detecting…
Active galactic nuclei (AGN) have been proposed as environments that can facilitate the capture of extreme-mass-ratio binaries and accelerate their inspiral beyond the rate expected from gravitational wave emission alone. In this work, we…
Forthcoming advances in direct gravitational wave detection from kilohertz to nanohertz frequencies have unique capabilities to detect signatures from or set meaningful constraints on a wide range of new cosmological phenomena and new…
LISA is a planned space-based gravitational-wave (GW) detector that would be sensitive to waves from low-frequency sources, in the band of roughly (0.03 - 0.1) mHz < f < 0.1 Hz. This is expected to be an extremely rich chunk of the GW…
Observations of a merging neutron star binary in both gravitational waves, by the Laser Interferometer Gravitational-wave Observatory (LIGO), and across the spectrum of electromagnetic radiation, by myriad telescopes, have been used to show…