A5029282591- Pulsars and Gravitational Waves Research
- Gamma-ray bursts and supernovae
- Cosmology and Gravitation Theories
- Geophysics and Gravity Measurements
- Astrophysical Phenomena and Observations
- High-pressure geophysics and materials
- Seismic Waves and Analysis
- Atomic and Subatomic Physics Research
- Particle physics theoretical and experimental studies
- Radio Astronomy Observations and Technology
- Dark Matter and Cosmic Phenomena
- Geophysics and Sensor Technology
- Astrophysics and Cosmic Phenomena
- Statistical and numerical algorithms
- Black Holes and Theoretical Physics
- Seismic Imaging and Inversion Techniques
- Superconducting and THz Device Technology
- Cold Atom Physics and Bose-Einstein Condensates
- Radiology practices and education
- Adaptive optics and wavefront sensing
- Magnetic confinement fusion research
King's College London
2021-2025
University College London
2021-2024
University of London
2021-2024
Universidad de Londres
2024
We report on the population properties of compact binary mergers inferred from gravitational-wave observations these systems during first three LIGO-Virgo observing runs. The Gravitational-Wave Transient Catalog 3 (GWTC-3) contains signals consistent with classes mergers: black hole, neutron star, and star–black hole mergers. infer star merger rate to be between 10 <a:math xmlns:a="http://www.w3.org/1998/Math/MathML" display="inline"><a:mrow><a:mn>1700</a:mn><a:mtext> </a:mtext><a:mtext>...
The second Gravitational-Wave Transient Catalog, GWTC-2, reported on 39 compact binary coalescences observed by the Advanced LIGO and Virgo detectors between 1 April 2019 15∶00 UTC October UTC. Here, we present GWTC-2.1, which reports a deeper list of candidate events over same period. We analyze final version strain data this period with improved calibration better subtraction excess noise, has been publicly released. employ three matched-filter search pipelines for identification, estimate...
Abstract The Einstein Telescope (ET), the European project for a third-generation gravitational-wave detector, has reference configuration based on triangular shape consisting of three nested detectors with 10 km arms, where each detector 'xylophone' made an interferometer tuned toward high frequencies, and low frequencies working at cryogenic temperature. Here, we examine scientific perspectives under possible variations this design. We perform detailed evaluation science case single...
The second Gravitational-Wave Transient Catalog reported on 39 compact binary coalescences observed by the Advanced LIGO and Virgo detectors between 1 April 2019 15:00 UTC October UTC. We present GWTC-2.1, which reports a deeper list of candidate events over same period. analyze final version strain data this period with improved calibration better subtraction excess noise, has been publicly released. employ three matched-filter search pipelines for identification, estimate astrophysical...
The global network of gravitational-wave observatories now includes five detectors, namely LIGO Hanford, Livingston, Virgo, KAGRA, and GEO 600. These detectors collected data during their third observing run, O3, composed three phases: O3a starting in April 2019 lasting six months, O3b November O3GK 2020 2 weeks. In this paper we describe these various other science products that can be freely accessed through the Gravitational Wave Open Science Center at https://gwosc.org. main dataset,...
We use 47 gravitational-wave sources from the Third LIGO-Virgo-KAGRA Gravitational-Wave Transient Catalog (GWTC-3) to estimate Hubble parameter $H(z)$, including its current value, constant $H_0$. Each (GW) signal provides luminosity distance source and we corresponding redshift using two methods: redshifted masses a galaxy catalog. Using binary black hole (BBH) masses, simultaneously infer mass distribution $H(z)$. The displays peak around $34\, {\rm M_\odot}$, followed by drop-off....
This paper describes the first all-sky search for long-duration, quasi-monochromatic gravitational-wave signals emitted by ultralight scalar boson clouds around spinning black holes using data from third observing run of Advanced LIGO. We analyze frequency range 20~Hz to 610~Hz, over a small derivative zero, and use multiple resolutions be robust towards possible signal wanderings. Outliers this are followed up two different methods, one more suitable nearly monochromatic signals, other...
We report the observation of a coalescing compact binary with component masses $2.5\text{-}4.5~M_\odot$ and $1.2\text{-}2.0~M_\odot$ (all measurements quoted at 90% credible level). The gravitational-wave signal GW230529_181500 was observed during fourth observing run LIGO-Virgo-KAGRA detector network on 2023 May 29 by LIGO Livingston Observatory. primary source has mass less than $5~M_\odot$ 99% credibility. cannot definitively determine from data alone whether either is neutron star or...
Abstract We report the observation of a coalescing compact binary with component masses 2.5–4.5 M ⊙ and 1.2–2.0 (all measurements quoted at 90% credible level). The gravitational-wave signal GW230529_181500 was observed during fourth observing run LIGO–Virgo–KAGRA detector network on 2023 May 29 by LIGO Livingston observatory. primary source has mass less than 5 99% credibility. cannot definitively determine from data alone whether either is neutron star or black hole. However, given...
We present a search for dark photon matter that could couple to gravitational-wave interferometers using data from Advanced LIGO and Virgo's third observing run. To perform this analysis, we use two methods, one based on cross-correlation of the strain channels in nearly aligned detectors, looks excess power Virgo detectors. The method optimizes Fourier Transform coherence time as function frequency, account expected signal width due Doppler modulations. do not find any evidence with mass...
Abstract Isolated neutron stars that are asymmetric with respect to their spin axis possible sources of detectable continuous gravitational waves. This paper presents a fully coherent search for such signals from eighteen pulsars in data LIGO and Virgo’s third observing run (O3). For known pulsars, efficient sensitive matched-filter searches can be carried out if one assumes the radiation is phase-locked electromagnetic emission. In presented here, we relax this assumption allow both...
We present a targeted search for continuous gravitational waves (GWs) from 236 pulsars using data the third observing run of LIGO and Virgo (O3) combined with second (O2). Searches were emission $l=m=2$ mass quadrupole mode frequency at only twice pulsar rotation (single harmonic) $l=2, m=1,2$ modes both once (dual harmonic). No evidence GWs was found so we 95\% credible upper limits on strain amplitudes $h_0$ single harmonic along pulsars' moments $Q_{22}$ ellipticities $\varepsilon$. Of...
We present a directed search for continuous gravitational wave (CW) signals emitted by spinning neutron stars located in the inner parsecs of Galactic Center (GC). Compelling evidence presence numerous population has been reported literature, turning this region into very interesting place to look CWs. In search, data from full O3 LIGO-Virgo run detector frequency band $[10,2000]\text{ }\text{ }\mathrm{Hz}$ have used. No significant detection was found and 95% confidence level upper limits...
Results are presented of searches for continuous gravitational waves from 20 accreting millisecond X-ray pulsars with accurately measured spin frequencies and orbital parameters, using data the third observing run Advanced LIGO Virgo detectors. The search algorithm uses a hidden Markov model, where transition probabilities allow frequency to wander according an unbiased random walk, while $\mathcal{J}$-statistic maximum-likelihood matched filter tracks binary phase. Three narrow sub-bands...
Abstract We report the results of first joint observation KAGRA detector with GEO 600. is a cryogenic and underground gravitational-wave consisting laser interferometer 3 km arms, located in Kamioka, Gifu, Japan. 600 British–German m near Hannover, Germany. performed observing run from April 7 to 20, 2020. present analysis GEO–KAGRA data for transient signals, including coalescence neutron-star binaries generic unmodeled transients. also perform dedicated searches binary signals transients...
ABSTRACT We describe a search for gravitational waves from compact binaries with at least one component mass $0.2$–$1.0 \, \mathrm{M}_\odot$ and ratio q ≥ 0.1 in Advanced Laser Interferometer Gravitational-Wave Observatory (LIGO) Virgo data collected between 2019 November 1, 15:00 utc 2020 March 27, 17:00 utc. No signals were detected. The most significant candidate has false alarm rate of $0.2 \rm {yr}^{-1}$. estimate the sensitivity our over entirety LIGO’s Virgo’s third observing run,...
This paper presents the results of a search for generic short-duration gravitational-wave transients in data from third observing run Advanced LIGO and Virgo. Transients with durations milliseconds to few seconds 24--4096 Hz frequency band are targeted by search, no assumptions made regarding incoming signal direction, polarization or morphology. Gravitational waves compact binary coalescences that have been identified other analyses detected, but statistically significant evidence...
Results are presented for a semi-coherent search continuous gravitational waves from the low-mass X-ray binary Scorpius X-1, using hidden Markov model (HMM) to allow spin wandering. This improves on previous HMM-based searches of Laser Interferometer Gravitational-wave Observatory (LIGO) data by including orbital period in template grid, and analyzing latest (third) observing run (O3). In frequency range searched, 60 500 Hz, we find no evidence radiation. is most sensitive X-1 HMM date. For...
We search for gravitational-wave signals associated with gamma-ray bursts detected by the Fermi and Swift satellites during second half of third observing run Advanced LIGO Virgo (1 November 2019 15:00 UTC-27 March 2020 17:00 UTC).We conduct two independent searches: a generic transients to analyze 86 an analysis target binary mergers at least one neutron star as short burst progenitors 17 events. find no significant evidence any these bursts. A weighted binomial test combined results finds...
We investigate the reach of LIGO/Virgo/KAGRA detectors in search for signatures first-order phase transitions early Universe. Utilizing data from first three observing runs, we derive constraints on parameters underlying gravitational-wave background, focusing characterized by strong supercooling. As an application our analysis, determine bounds parameter space two representative particle physics models. also comment expected third-generation probing supercooled transitions.
After the detection of gravitational waves from compact binary coalescences, search for transient gravitational-wave signals with less well-defined waveforms which matched filtering is not well suited one frontiers astronomy. Broadly classified into ``short'' $\ensuremath{\lesssim}1\text{ }\text{ }\mathrm{s}$ and ``long'' $\ensuremath{\gtrsim}1\text{ duration signals, these are expected a variety astrophysical processes, including non-axisymmetric deformations in magnetars or eccentric black...
We present the first results from an all-sky all-frequency (ASAF) search for anisotropic stochastic gravitational-wave background using data three observing runs of Advanced LIGO and Virgo detectors. Upper limit maps on broadband anisotropies a persistent were published all LIGO-Virgo However, analysis is likely to miss narrowband signals as signal-to-noise ratio signal can be significantly reduced when combined with detector output other frequencies. Data folding computationally efficient...
Abstract We present Fermi Gamma-ray Burst Monitor (Fermi-GBM) and Swift Alert Telescope (Swift-BAT) searches for gamma-ray/X-ray counterparts to gravitational-wave (GW) candidate events identified during the third observing run of Advanced LIGO Virgo detectors. Using Fermi-GBM onboard triggers subthreshold gamma-ray burst (GRB) candidates found in ground analyses, Targeted Search Untargeted Search, we investigate whether there are any coincident GRBs associated with GWs. also search...
Current gravitational wave (GW) detection pipelines for compact binary coalescence based on matched-filtering have reported over 90 confident detections during the first three observing runs of LIGO-Virgo-KAGRA (LVK) detector network. Decreasing latency detection, in particular future detectors anticipated to high rates, remains an ongoing effort. In this paper, we develop and test a sparse dictionary learning (SDL) algorithm rapid GWs. We evaluate algorithms biases estimate its GW rate...
Continuous gravitational waves (CWs) emission from neutron stars carries information about their internal structure and equation of state, it can provide tests General Relativity. We present a search for CWs set 45 known pulsars in the first part fourth LIGO--Virgo--KAGRA observing run, as O4a. conducted targeted each pulsar using three independent analysis methods considering single-harmonic dual-harmonic models. find no evidence CW signal O4a data both models upper limits on amplitude...