Exploring the Gravitational-wave Universe
Lead Research Organisation:
CARDIFF UNIVERSITY
Department Name: School of Physics and Astronomy
Abstract
The era of gravitational-wave (GW) astronomy began in 2015 with LIGO's detection of the binary black-hole merger event GW150914, at the time the most energetic event ever observed by humanity. The announcement of this spectacular event generated headlines worldwide and led to the award of the 2017 Nobel Prize in Physics. More detections followed, including the now-famous binary neutron star merger event GW170817 associated with GRB170817A - the first multi-messenger gravitational-wave event. To date LIGO and VIRGO have published the details of 15 high-confidence detections and released public alerts for more than 50 additional candidate signals.
Cardiff University researchers in the Gravity Exploration Institute (GEI) have made critical contributions to these detections and to the opening of the gravitational-wave sky. Together, the research of the GEI spans the entire breadth of gravitational-wave astronomy, from fundamental research into instruments, the modelling, detection and interpretation of events, and implications for fundamental physics, astrophysics, and cosmology. The GEI has grown to become the fourth largest group in the LIGO Scientific Collaboration (LSC), and our members provide leadership through a number of key strategic roles.
We propose an ambitious programme that will have impacts across the breadth of gravitational-wave astronomy. This includes the development of advanced technology for future detectors, the creation of the most accurate state-of-the-art models for binary black hole signals, cutting edge techniques for real-time analysis of the LIGO-Virgo-KAGRA data, fast and accurate characterisation of sources, and mapping gravitational-wave observations into new insights into astrophysics, cosmology, and fundamental physics.
Our experimental program focuses on technologies critical for upgrades to the current LIGO detectors and for next-generation observatories. We will increase the detector up-time and data quality by improving the seismic feedback control systems and implementing real time adaptive controls. We will develop lower-loss methods to reduce the noise in LIGO below the standard quantum limit and explore how co-located interferometers may further improve sensitivity. And we will pave the way for next-generation cryogenic detectors by building an input-output optics prototype operating at longer wavelengths, requiring the exploration of new lasers and optics.
Our modelling, analysis, and astrophysics programme will benefit from synergy between the projects, yielding more precise source characterisation and astrophysical interpretations.
We will perform the deepest analysis of the LIGO-Virgo data for gravitational-wave counterparts to gamma-ray bursts like GRB170817A. We will push the limits of multi-messenger astronomy by using machine learning techniques to detect generic transient signals such as supernovae, binary mergers, and accretion disk instabilities with sub-second latencies, enabling follow-up observations to catch the earliest electromagnetic emissions from these events.
The ever increasing detection rates will allow us to explore further across the parameter space of compact binaries populations, including more rare events, but also require ever faster means of characterising detected signals. We will develop semi-analytical tools to provide an intuitive understanding of parameter estimation, allowing the prompt identification of exceptional events.
We will implement complete, accurate, and fast inference techniques pioneered at Cardiff and apply then to infer neutron star equation of state. We will further develop tools to infer astrophysical populations from our observations and provide real-time updates to population models.
Finally, we will compare the observed populations with astrophysical formation scenarios, exploiting the unprecedented data set and physically motivated models of binary populations, to infer the origins of gravitational waves.
Cardiff University researchers in the Gravity Exploration Institute (GEI) have made critical contributions to these detections and to the opening of the gravitational-wave sky. Together, the research of the GEI spans the entire breadth of gravitational-wave astronomy, from fundamental research into instruments, the modelling, detection and interpretation of events, and implications for fundamental physics, astrophysics, and cosmology. The GEI has grown to become the fourth largest group in the LIGO Scientific Collaboration (LSC), and our members provide leadership through a number of key strategic roles.
We propose an ambitious programme that will have impacts across the breadth of gravitational-wave astronomy. This includes the development of advanced technology for future detectors, the creation of the most accurate state-of-the-art models for binary black hole signals, cutting edge techniques for real-time analysis of the LIGO-Virgo-KAGRA data, fast and accurate characterisation of sources, and mapping gravitational-wave observations into new insights into astrophysics, cosmology, and fundamental physics.
Our experimental program focuses on technologies critical for upgrades to the current LIGO detectors and for next-generation observatories. We will increase the detector up-time and data quality by improving the seismic feedback control systems and implementing real time adaptive controls. We will develop lower-loss methods to reduce the noise in LIGO below the standard quantum limit and explore how co-located interferometers may further improve sensitivity. And we will pave the way for next-generation cryogenic detectors by building an input-output optics prototype operating at longer wavelengths, requiring the exploration of new lasers and optics.
Our modelling, analysis, and astrophysics programme will benefit from synergy between the projects, yielding more precise source characterisation and astrophysical interpretations.
We will perform the deepest analysis of the LIGO-Virgo data for gravitational-wave counterparts to gamma-ray bursts like GRB170817A. We will push the limits of multi-messenger astronomy by using machine learning techniques to detect generic transient signals such as supernovae, binary mergers, and accretion disk instabilities with sub-second latencies, enabling follow-up observations to catch the earliest electromagnetic emissions from these events.
The ever increasing detection rates will allow us to explore further across the parameter space of compact binaries populations, including more rare events, but also require ever faster means of characterising detected signals. We will develop semi-analytical tools to provide an intuitive understanding of parameter estimation, allowing the prompt identification of exceptional events.
We will implement complete, accurate, and fast inference techniques pioneered at Cardiff and apply then to infer neutron star equation of state. We will further develop tools to infer astrophysical populations from our observations and provide real-time updates to population models.
Finally, we will compare the observed populations with astrophysical formation scenarios, exploiting the unprecedented data set and physically motivated models of binary populations, to infer the origins of gravitational waves.
Organisations
Publications
Abbott R
(2022)
All-sky search for continuous gravitational waves from isolated neutron stars using Advanced LIGO and Advanced Virgo O3 data
in Physical Review D
Abbott R
(2022)
Search for continuous gravitational wave emission from the Milky Way center in O3 LIGO-Virgo data
in Physical Review D
Abbott R
(2022)
Model-based Cross-correlation Search for Gravitational Waves from the Low-mass X-Ray Binary Scorpius X-1 in LIGO O3 Data
in The Astrophysical Journal Letters
Abbott R
(2022)
Narrowband Searches for Continuous and Long-duration Transient Gravitational Waves from Known Pulsars in the LIGO-Virgo Third Observing Run
in The Astrophysical Journal
Abbott R
(2021)
Upper limits on the isotropic gravitational-wave background from Advanced LIGO and Advanced Virgo's third observing run
in Physical Review D
Abbott R
(2022)
Search for gravitational waves from Scorpius X-1 with a hidden Markov model in O3 LIGO data
in Physical Review D
Abbott R
(2021)
Diving below the Spin-down Limit: Constraints on Gravitational Waves from the Energetic Young Pulsar PSR J0537-6910
in The Astrophysical Journal Letters
Abbott R
(2021)
Population Properties of Compact Objects from the Second LIGO-Virgo Gravitational-Wave Transient Catalog
in The Astrophysical Journal Letters
Abbott R
(2023)
Constraints on the Cosmic Expansion History from GWTC-3
in The Astrophysical Journal
Abbott R
(2021)
All-sky search in early O3 LIGO data for continuous gravitational-wave signals from unknown neutron stars in binary systems
in Physical Review D
Abbott R
(2022)
Search for Subsolar-Mass Binaries in the First Half of Advanced LIGO's and Advanced Virgo's Third Observing Run.
in Physical review letters
Abbott R
(2021)
Constraints from LIGO O3 Data on Gravitational-wave Emission Due to R-modes in the Glitching Pulsar PSR J0537-6910
in The Astrophysical Journal
Abbott R
(2022)
Searches for Gravitational Waves from Known Pulsars at Two Harmonics in the Second and Third LIGO-Virgo Observing Runs
in The Astrophysical Journal
Abbott R
(2021)
All-sky search for long-duration gravitational-wave bursts in the third Advanced LIGO and Advanced Virgo run
in Physical Review D
Abbott R.
Open Data from the Third Observing Run of LIGO, Virgo, KAGRA, and GEO
in Astrophysical Journal, Supplement Series
Aiello L
(2022)
Constraints on Scalar Field Dark Matter from Colocated Michelson Interferometers
in Physical Review Letters
Barber J
(2024)
Black hole binary mergers in dense star clusters: the importance of primordial binaries
in Monthly Notices of the Royal Astronomical Society
Belczynski K
(2022)
Black hole - black hole total merger mass and the origin of LIGO/Virgo sources
Belczynski K
(2022)
Black Hole-Black Hole Total Merger Mass and the Origin of LIGO/Virgo Sources
in The Astrophysical Journal
Chattopadhyay D
(2023)
Double black hole mergers in nuclear star clusters: eccentricities, spins, masses, and the growth of massive seeds
in Monthly Notices of the Royal Astronomical Society
Chattopadhyay D
(2022)
Modelling the formation of the first two neutron star-black hole mergers, GW200105 and GW200115: metallicity, chirp masses, and merger remnant spins
in Monthly Notices of the Royal Astronomical Society
Collaboration T
(2021)
Upper Limits on the Isotropic Gravitational-Wave Background from Advanced LIGO's and Advanced Virgo's Third Observing Run
in arXiv e-prints
Collaboration T
(2021)
Constraints on cosmic strings using data from the third Advanced LIGO-Virgo observing run
in arXiv e-prints