A5080598601- Pulsars and Gravitational Waves Research
- Gamma-ray bursts and supernovae
- Geophysics and Gravity Measurements
- Astrophysical Phenomena and Observations
- Cosmology and Gravitation Theories
- High-pressure geophysics and materials
- Astrophysics and Cosmic Phenomena
- Atomic and Subatomic Physics Research
- Stellar, planetary, and galactic studies
- Seismic Waves and Analysis
- Geophysics and Sensor Technology
- Radio Astronomy Observations and Technology
- Astronomy and Astrophysical Research
- Statistical and numerical algorithms
- Magnetic confinement fusion research
- Astronomical Observations and Instrumentation
- earthquake and tectonic studies
- Adaptive optics and wavefront sensing
- Dark Matter and Cosmic Phenomena
- Black Holes and Theoretical Physics
- Astro and Planetary Science
- GNSS positioning and interference
- Hydraulic Fracturing and Reservoir Analysis
- Solar and Space Plasma Dynamics
- Methane Hydrates and Related Phenomena
University of Wisconsin–Milwaukee
2021-2024
Rochester Institute of Technology
2017-2023
All ten LIGO/Virgo binary black hole (BH-BH) coalescences reported following the O1/O2 runs have near-zero effective spins. There are only three potential explanations for this. If BH spin magnitudes large, then: (i) either both vectors must be nearly in orbital plane or (ii) angular momenta of BHs oppositely directed and similar magnitude. Then there is also possibility that (iii) small. We consider third hypothesis within framework classical isolated evolution scenario BH-BH merger...
We study the expected spin misalignments of merging binary black holes formed in isolation by combining state-of-the-art population-synthesis models with efficient post-Newtonian evolutions, thus tracking sources from stellar formation to gravitational-wave detection. present extensive predictions properties detectable both current and future interferometers. account for fact that detectors are more sensitive spinning black-hole binaries suitable orientations find this significantly impacts...
Gravitational wave measurements will provide insight into the population of coalescing compact binaries throughout universe. We describe and demonstrate a flexible parametric method to infer event rate as function binary parameters, accounting for Poisson error selection biases. Using concrete synthetic data based on projections LIGO Virgo's O3 run, we discuss how well GW could constrain mass spin distribution neutron stars black holes in near future, within context several phenomenological...
ABSTRACT Accretion discs around supermassive black holes are promising sites for stellar mass hole mergers detectable with LIGO. Here we present the results of Monte Carlo simulations within 1-d AGN disc models. For spin distribution in bulk, key findings are: (1) The χeff is naturally centred $\tilde{\chi }_{\rm eff} \approx 0.0$, (2) width narrow low natal spins. (3) ratios $\tilde{q} \sim 0.5\!-\!0.7$, (4) maximum merger bulk $\sim 100\!-\!200\, \mathrm{M}_{\odot }$, (5) 1{{\ \rm per\...
Data from the LIGO and Virgo detectors has confirmed that stellar-mass black holes can merge within a Hubble time, leaving behind massive remnant holes. In some astrophysical environments such as globular clusters AGN disks, it may be possible for these remnants to take part in further compact-object mergers, producing population of hierarchically formed this work, we present parameterized framework describing binary hole while self-consistently accounting hierarchical mergers. The casts...
Multimessenger searches for binary neutron star (BNS) and star-black hole (NSBH) mergers are currently one of the most exciting areas astronomy. The search joint electromagnetic neutrino counterparts to gravitational wave (GW)s has resumed with ALIGO’s, AdVirgo’s KAGRA’s fourth observing run (O4). To support this effort, public semiautomated data products sent in near real-time include localization source properties guide complementary observations. In preparation O4, we have conducted a...
We compare binary evolution models with different assumptions about black-hole natal kicks to the first gravitational-wave observations performed by LIGO detectors. Our comparisons attempt reconcile merger rate, masses, spins, and spin-orbit misalignments of all current state-of-the-art formation scenarios black holes formed in isolation. estimate that (BHs) should receive at birth order $\sigma\simeq 200$ (50) km/s if tidal processes do (not) realign stellar spins. is driven two simple...
The inferred parameters of the binary black hole GW151226 are consistent with nonzero spin for most massive hole, misaligned from binary's orbital angular momentum. If holes formed through isolated evolution an initially aligned star, this misalignment would then arise a natal kick imparted to first-born at its birth during stellar collapse. We use simple kinematic arguments constrain characteristic magnitude kick, and find that vk≳50 km/s must be produce misalignments GW151226. Such large...
We use population inference to explore the impact that uncertainties in distribution of binary black holes (BBH) have on astrophysical gravitational-wave background (AGWB). Our results show AGWB monopole is sensitive nature BBH (particularly local merger rate), while anisotropic $C_\ell$ spectrum only modified within a few percent, at level which insignificant compared other sources uncertainty (such as cosmic variance). This very promising news for future observational studies AGWB, it...
Gravitational wave Bayesian parameter inference involves repeated comparisons of gravitational data to generic candidate predictions. Even with algorithmically efficient methods such as RIFT or reduced-order quadrature, the time needed perform these calculations and overall computational cost can be significant compared minutes hours achieve goals low-latency multimessenger astronomy. By translating some elements algorithm operate on graphics processing units, we demonstrate substantial...
Over the past year, a handful of new gravitational wave models have been developed to include multiple harmonic modes thereby enabling for first time fully Bayesian inference studies including higher be performed. Using one recently numerical relativity surrogate model, NRHybSur3dq8, we investigate importance on parameter coalescing massive binary black holes. We focus examples relevant current three-detector network observatories, with detector-frame mass set $120\text{ }\text{...
The LIGO Scientific, Virgo and KAGRA Collaborations recently released the third gravitational wave transient catalog or GWTC-3, significantly expanding number of signals. To address the---still uncertain---formation channels source compact binaries, their population properties must be characterized. computational cost Bayesian hierarchical methods employed thus far scales with size event catalogs, such have until assumed fixed functional forms for distribution. Here we propose a fast...
The rapid iterative fitting (RIFT) parameter inference algorithm provides a framework for efficient, highly parallelized GW sources. In this paper, we summarize essential enhancements and operating point choices the RIFT algorithm, including settings used analysis of LIGO/Virgo O3 observations. We also describe other extensions to software ecosystem. Some increase RIFT's flexibility produce outputs pertinent astrophysics. Other its computational efficiency or stability. Using many randomly...
Abstract The astrophysical origin of over 90 compact binary mergers discovered by the LIGO and Virgo gravitational wave observatories is an open question. While unusual mass spin some objects constrain progenitor scenarios, observed are consistent with multiple interpretations. A promising approach to solve this question consider distributions properties compare them expectations from different scenarios. Here we describe a new hierarchical population analysis framework assess relative...
Observations of the properties multiple coalescing neutron stars will simultaneously provide insight into star mass and spin distribution, merger rate, nuclear equation state. Not all merging binaries containing are expected to be identical. Plausible sources diversity in these can arise from a broad or multi-peaked NS distribution; effect different extreme natal spins; possibility NS-BH mergers; even phase transitions, allowing for with similar but strongly divergent radius. In this work,...
We determine the geometrical and viewing angle parameters of Large Magellanic Cloud (LMC) using Leavitt law based on a sample more than $3500$ common classical Cepheids (FU FO) in optical ($V,I$), near-infrared ($JHK_{s}$) mid-infrared ($[3.6]~\mu$m $[4.5]~\mu$m) photometric bands. Statistical reddening distance modulus free from effect to each individual are obtained simultaneous multi-band fit apparent moduli analysis resulting laws these seven A map LMC shows good agreement with other...
The astrophysical origin of the over 90 compact binary mergers discovered by LIGO and Virgo gravitational wave observatories is an open question. While unusual mass spin some objects constrain progenitor scenarios, observed are consistent with multiple interpretations. A promising approach to solve this question consider distributions properties compare them expectations from different scenarios. Here we describe a new hierarchical population analysis framework assess relative contribution...
Gravitational-wave observations have the capability to strongly differentiate between different assumptions for how binary compact objects form. The agreement of models evolution massive stellar binaries leading formation can be characterized by a Bayesian marginal likelihood. In this work, we show carefully interpolate likelihood choices model parameters, enabling analysis their posterior distributions expensive simulations. Using startrack code, compare one- and four-dimensional mergers...
Multi-messenger searches for BNS and NSBH mergers are currently one of the most exciting areas astronomy. The search joint electromagnetic neutrino counterparts to GWs has resumed with O4. To support this effort, public semi-automated data products sent in near real-time include localization source properties guide complementary observations. In preparation O4, we have conducted a study using simulated population compact binaries MDC form replay optimize profile software infrastructure...
We offer a brief response to the criticisms put forward by Cusin et al in arXiv:1811.03582 about our work arXiv:1810.13435 and arXiv:1806.01718, emphasising that none of these are relevant main results.
The LIGO Scientific, Virgo and KAGRA Collaborations recently released the third gravitational wave transient catalog or GWTC-3, significantly expanding number of (GW) signals. To address -- still uncertain formation channels source compact binaries, their population properties must be characterized. computational cost Bayesian hierarchical methods employed thus far scales with size event catalogs, such have until assumed fixed functional forms for distribution. Here we propose a fast...
We are living through the dawn of era gravitational wave astronomy. Our first glances this new window upon sky has revealed a population objects. Since it began observing in late 2015, advanced Laser Interferometer Gravitational-Wave Observatory (LIGO) detected waves three times, along with an additional strong candidate -- and there shall be orders magnitude more years to come. In all four cases, waveform's signature is consistent general relativity's predictions for merging two black...
Gravitational waves from inspiralling neutron stars carry information about matter at extreme gravity and density. The binary star (BNS) event GW170817 provided, for the first time, insight into dense through this window. Since then, another BNS (GW190425) several star-black hole events have been detected, although tidal measurements were not expected to be well-constrained them. Collective regarding behavior of nuclear densities can done by performing a joint population inference masses,...