Related papers: Ringdown bounds and spectral density limits from G…
Using recent experimental results of detection of gravitational waves from the binary black hole signals by Advanced LIGO and Advanced Virgo, we investigate the propagation of gravitational waves in the context of fourth order gravity…
We search for nearly-monochromatic gravitational wave signals with frequencies $800.0~\textrm{Hz} \leq f \leq 1686.0~\textrm{Hz}$ and spin-down $-2.7\times10^{-9}~\textrm{Hz}\,\textrm{s}^{-1} \leq \dot f \leq 0.2\times…
The ringdown phase of a gravitational wave signal from a binary black hole merger offers a unique laboratory for testing general relativity in the strong-field regime and probing the properties of the final remnant black hole. In this…
We infer recoil (kick) velocities for all binary black hole merger events reported up to the GWTC--4 catalog, together with candidate intermediate-mass black hole events. We obtain informative kick constraints for GW231028\_153006…
We present a directed search for continuous gravitational wave (CW) signals emitted by spinning neutron stars located in the inner parsecs of the Galactic Center (GC). Compelling evidence for the presence of a numerous population of neutron…
The ringdown phase of a binary black hole merger is modelled by the quasi-normal modes of a perturbed Kerr black hole. According to the black hole no-hair theorem, the emitted ringdown spectra are constrained by the mass and spin of the…
Dense astrophysical environments like globular clusters and galactic nuclei can host hyperbolic encounters of black holes which can lead to gravitational-wave driven capture. There are several astrophysical models which predict a fraction…
A discovery of gravitational waves from binary black holes raises a possibility that measurements of them can provide strict tests of CPT invariance in gravitational waves. When CPT violation exists, if any, gravitational waves with…
We perform the first nonlinear and self-consistent study of the merger and ringdown of a black hole mimicking object with stable light rings. To that end, we numerically solve the full Einstein-Klein-Gordon equations governing the head-on…
The cosmic expansion rate can be directly measured with gravitational-wave (GW) data of the compact binary mergers by jointly constraining the mass function of the population and the cosmological model via the so-called spectral sirens.…
Gravitational wave standard sirens offer a promising avenue for cosmological inference, particularly in measuring the expansion history of the universe. Traditionally, bright sirens require an electromagnetic counterpart to determine the…
Black hole spectroscopy is the proposal to observe multiple quasinormal modes in the ringdown of a binary black hole merger. In addition to the fundamental quadrupolar mode, overtones and higher harmonics may be present and detectable in…
The detection of quadratic quasi-normal modes would provide a direct probe into black hole nonlinear perturbations. We report the first observational evidence of a set of quadratic quasi-normal modes in the gravitational-wave ringdown of a…
We report results of a deep all-sky search for periodic gravitational waves from isolated neutron stars in data from the S6 LIGO science run. The search was possible thanks to the computing power provided by the volunteers of the…
Gravitational waves from the explosive merger of distant black holes are encoded with details regarding the complex extreme-gravity spacetime present at their source. Famously described by the Kerr spacetime metric for rotating black holes…
Theories beyond general relativity (GR) modify the propagation of gravitational waves (GWs). In some, inhomogeneities (aka. gravitational lenses) allow interactions between the metric and additional fields to cause lens-induced…
Whether astrophysical black holes (BHs) can have charge is a question to be addressed by observations. In the era of gravitational wave (GW) astronomy, one can constrain the charge of a merged BH remnant using the merger-ringdown signal of…
We use the data of several promising gravitational wave observations to obtain increasingly stringent bounds on near-horizon deviations of their sources from the Kerr geometry. A range of horizonless compact objects proposed as alternatives…
We analyze gravitational-wave data from the first LIGO detection of a binary black-hole merger (GW150914) in search of the ringdown of the remnant black hole. Using observations beginning at the peak of the signal, we find evidence of the…
The gravitational-wave signal GW170817 is a result of a binary neutron star coalescence event. The observations of electromagnetic counterparts suggest that the event didn't led to the prompt formation of a black-hole. In this work, we…