A5107987768- Pulsars and Gravitational Waves Research
- Gamma-ray bursts and supernovae
- Astrophysical Phenomena and Observations
- Cosmology and Gravitation Theories
- Geophysics and Gravity Measurements
- High-pressure geophysics and materials
- Radio Astronomy Observations and Technology
- Geophysics and Sensor Technology
- Astrophysics and Cosmic Phenomena
- Relativity and Gravitational Theory
- Atomic and Subatomic Physics Research
- Seismic Waves and Analysis
- Cold Atom Physics and Bose-Einstein Condensates
- Dark Matter and Cosmic Phenomena
- Black Holes and Theoretical Physics
- Global Maternal and Child Health
- Magnetic confinement fusion research
- Seismology and Earthquake Studies
- Astronomical Observations and Instrumentation
- Superconducting Materials and Applications
- Computational Physics and Python Applications
- Statistical and numerical algorithms
- Child Nutrition and Water Access
- Noncommutative and Quantum Gravity Theories
- Space exploration and regulation
University of Mississippi
2020-2025
Gavi
2019-2022
Pennsylvania State University
2017-2021
Inter-University Centre for Astronomy and Astrophysics
2015-2019
California University of Pennsylvania
2019
Park University
2018
Gajara Raja Medical College
2018
University of Jammu
2018
Tata Institute of Fundamental Research
2014-2015
Government of India
2014
This Horizon Study describes a next-generation ground-based gravitational-wave observatory: Cosmic Explorer. With ten times the sensitivity of Advanced LIGO, Explorer will push astronomy towards edge observable universe ($z \sim 100$). The goals this are to describe and evaluate design concepts for Explorer; plan United States' leadership in astronomy; envisage role international effort build "Third-Generation" (3G) observatory network that make discoveries transformative across astronomy,...
After their successful first observing run (September 12, 2015 - January 2016), the Advanced LIGO detectors were upgraded to increase sensitivity for second (November 30, 2016 August 26, 2017). The Virgo detector joined on 1, 2017. We discuss updates that happened during this period in GstLAL-based inspiral pipeline, which is used detect gravitational waves from coalescence of compact binaries both low latency and an offline configuration. These include deployment a zero-latency whitening...
Merger rates of binary black holes, neutron stars, and neutron-star--black-hole binaries in the local Universe (i.e., redshift $z=0$), inferred from Laser Interferometer Gravitational Wave Observatory Virgo, are $16\ensuremath{-}130\text{ }\text{ }{\mathrm{Gpc}}^{\ensuremath{-}3}\text{ }{\mathrm{yr}}^{\ensuremath{-}1}$, $13\ensuremath{-}1900\text{ $7.4\ensuremath{-}320\text{ respectively. These suggest that there is a significant chance two or more these signals will overlap with each other...
In this Letter, we show that multiband observations of stellar-mass binary black holes by the next generation ground-based observatories (3G) and space-based Laser Interferometer Space Antenna (LISA) would facilitate a comprehensive test general relativity simultaneously measuring all post-Newtonian coefficients. Multiband measure most known phasing coefficients to an accuracy below few percent-2 orders-of-magnitude better than best bounds achievable from even "golden" binaries in 3G or LISA...
The accumulation of certain types dark matter particles in neutron star cores due to accretion over long timescales can lead the formation a mini black hole. In this scenario, is destabilized and implodes form hole without significantly increasing its mass. When process occurs stars coalescing binaries, one or both might be converted before they merge. Thus, mass range $\sim \mbox{1--2}\, M_\odot,$ Universe contain three distinct populations compact binaries: containing only stars, second...
Detections of gravitational waves emitted from binary black hole coalescences allow us to probe the strong-field dynamics general relativity (GR). One can compare observed gravitational-wave signals with theoretical waveform models constrain possible deviations GR. Any physics that is not included in these might show up as apparent GR deviations. The used current tests describe binaries on quasicircular orbits, since most detected by ground-based detectors are expected have negligible...
Binary neutron-star mergers will predominantly produce black-hole remnants of mass $\ensuremath{\sim}3--4\text{ }\text{ }{M}_{\ensuremath{\bigodot}}$, thus populating the putative low-mass gap between neutron stars and stellar-mass black holes. If these holes are in dense astrophysical environments, segregation could lead to ``second-generation'' compact binaries merging within a Hubble time. In this paper, we investigate possible signatures such binary gravitational-wave observations. We...
Observation of gravitational waves (GWs) in two different frequency bands is referred to as multiband GW astronomy. With the planned Laser Interferometric Space Antenna (LISA) operating ${10}^{\ensuremath{-}4}--0.1\text{ }\text{ }\mathrm{Hz}$ range, and third-generation (3G) ground-based detectors such Cosmic Explorer (CE) Einstein Telescope (ET) $1--{10}^{4}\text{ astronomy could be a reality coming decades. In this paper, we present potential observations intermediate-mass binary black...
We propose a novel method to test the consistency of multipole moments compact binary systems with predictions general relativity (GR). The system, known in terms symmetric and trace-free tensors, are used calculate gravitational waveforms from binaries within post-Newtonian (PN) formalism. For nonspinning binaries, we derive wave phasing formula, frequency domain, parametrizing each PN order term which contribute that order. Using GW observations, this parametrized multipolar would allow us...
Two important parameters inferred from the gravitational wave signals of binaries precessing black holes are spin tilt angles, i.e., angles at which holes' axes inclined with respect to binary's orbital angular momentum. The LIGO-Virgo parameter estimation analyses provide tilts a fiducial reference frequency, often lowest frequency used in data analysis. However, most astrophysically interesting quantities when binary was formed, can be significantly different those for strongly binaries....
Gravitational wave (GW) measurements of physical effects such as spin-induced quadrupole moments can distinguish binaries consisting black holes from nonblack hole binaries. While these may be poorly constrained for single-event inferences with the second-generation detectors, combining information multiple detections help uncover features The moment has specific predictions different types compact objects, and a generalized formalism must consider population where objects co-exist. In this...
Abstract We propose a Bayesian inference framework to predict the merger history of LIGO-Virgo binary black holes (BHs), whose components may have undergone hierarchical mergers in past. The relies on numerical relativity predictions for mass, spin, and kick velocity remnant BHs. This proposed computes masses, spins, kicks imparted parent binaries, given initial masses spin magnitudes constituents. validate our approach by performing an “injection study” based constructed sequence...
General relativity (GR) has proven to be a highly successful theory of gravity since its inception. The thrivingly passed numerous experimental tests, predominantly in weak gravity, low relative speeds, and linear regimes, but also the strong-field very low-speed regimes with binary pulsars. Observable gravitational waves (GWs) originate from regions spacetime where is extremely strong, making them unique tool for testing GR, previously inaccessible large curvature, relativistic strong...
Compact binaries in hyperbolic orbits are plausible gravitational-wave (GW) sources for the upcoming and planned GW observatories. We develop an efficient prescription to compute post-Newtonian (PN)-accurate ready-to-use polarization states spinning compact binaries, influenced by dominant-order spin-orbit interactions, orbits. This is achieved invoking 1.5PN-accurate quasi-Keplerian parametrization radial sector of orbital dynamics. probe influences spins gravitational radiation reaction on...
In an earlier work [S. Kastha et al., Phys. Rev. D 98, 124033 (2018)], we developed the parametrized multipolar gravitational wave phasing formula to test general relativity, for nonspinning compact binaries in quasicircular orbit. this paper, extend method and include important effect of spins inspiral dynamics. Furthermore, consider parametric scaling post-Newtonian (PN) coefficients conserved energy binary, resulting nonprecessing spinning We also compute projected accuracies with which...
Gender-related barriers to immunization are key targets improve coverage and equity. We used individual-level demographic health survey data from 52 low- middle-income countries examine the relationship between women's social independence (measured by Survey-based Women's emPowERment (SWPER) Global Index) childhood immunization. The primary outcome was receipt of three doses diphtheria-tetanus-pertussis vaccine (DTP3) among children aged 12-35 months; we secondarily examined failure receive...
The spin orientations of spinning binary black hole (BBH) mergers detected by ground-based gravitational wave detectors such as LIGO and Virgo can provide important clues about the formation binaries. However, these tilts, i.e., angles between vector each binary's orbital angular momentum vector, change due to precessional effects holes evolve from a large separation their merger. tilts inferred at frequency in sensitive band comparing signal with theoretical waveforms thus be significantly...
Amplitude and phase of the gravitational waveform from compact binary systems can be decomposed in terms their mass- current-type multipole moments. In a modified theory gravity, one or more these moments could deviate general relativity. this work, we show that model parametrizes amplitude facilitate novel multiparameter test relativity with exquisite precision. Using network next-generation gravitational-wave observatories, simultaneous deviation leading seven multipoles GW190814-like...
Abstract Type Ia supernovae (SNe Ia) are among the pre-eminent distance ladders for precision cosmology due to their intrinsic brightness, which allows them be observable at high redshifts. Their usefulness as unbiased estimators of absolute cosmological distances, however, depends on accurate understanding or anchoring scale. This knowledge is based calibrating distances with Cepheids. Gravitational waves from compact binary coalescences, being standard sirens, can used validate SNe when...
Research question: Whether incidence of low birth weight has declined during last two decades? Objective: To study the and its association with maternal health correlates. Study design: Cross-sectional study. Predictor variables: Maternal diseases nutrition physical work past obstetric complications pregnancy utilization ANC services. Outcome variable: Birth newborn. Setting: Queen Mary Hospital; K.G. Medical College Lucknow. Participants: 889 mothers along their 901 newborns. Statistical...
We study precession dynamics of generic binary black holes in eccentric orbits using an effective potential based formalism derived [M. Kesden et al., PRL {\bf 114}, 081103 (2015)]. This is used to classify into three mutually exclusive spin morphologies. During the inspiral phase, binaries make transitions from one morphology others. evolve a population initial separation $1000\mathbf{M}$ final $10\mathbf{M}$ post-Newtonian accurate evolution equations. find that, given suitable conditions,...
Gravitational wave signals were recently detected directly by LIGO from the coalescences of two stellar mass black hole pairs. These detections have strengthened our long held belief that compact binary (CBCs) are most promising gravitational detection prospects accessible to ground-based interferometric detectors. For detecting CBC signals, it is vital importance characterize and identify non-Gaussian nonstationary noise in these In this work, we model important classes transient artifacts...