A5007083070- Pulsars and Gravitational Waves Research
- Cold Atom Physics and Bose-Einstein Condensates
- Astrophysical Phenomena and Observations
- Gamma-ray bursts and supernovae
- Geophysics and Gravity Measurements
- Atomic and Subatomic Physics Research
- Radio Astronomy Observations and Technology
- Cosmology and Gravitation Theories
- Quantum Chromodynamics and Particle Interactions
- Advanced Frequency and Time Standards
- Geophysics and Sensor Technology
- Relativity and Gravitational Theory
- Astronomy and Astrophysical Research
- Adaptive optics and wavefront sensing
- Astrophysics and Cosmic Phenomena
- Particle physics theoretical and experimental studies
- Spectroscopy and Laser Applications
- Seismic Waves and Analysis
- Astronomical Observations and Instrumentation
- Electronic and Structural Properties of Oxides
- Galaxies: Formation, Evolution, Phenomena
- Nonlinear Waves and Solitons
- Superconducting and THz Device Technology
- High-pressure geophysics and materials
- Material Science and Thermodynamics
University of Hong Kong
2023-2025
Chinese University of Hong Kong
2025
Sun Yat-sen University
2024
Peking University
2019-2023
Kavli Institute for Theoretical Sciences
2019-2023
Technische Universität Berlin
2016
Humboldt-Universität zu Berlin
2016
GW190521, the most massive binary black hole merger confidently detected by LIGO-Virgo-KAGRA Collaboration, is first gravitational-wave observation of an intermediate-mass hole. The signal was followed approximately 34 days later flare ZTF19abanrhr, in AGN $\mathrm{J}124942.3+344929$ Zwicky Transient Facility at 78% spatial contour for GW190521's sky localization. Using GWTC-2.1 data release, we find that association between GW190521 and ZTF19abanrhr as its electromagnetic counterpart...
Intermediate-mass ratio inspirals (IMRIs) formed by stellar-mass compact objects orbiting intermediate-mass black holes will be detected future gravitational wave (GW) observatories like TianQin, LISA, and AION. We study a set of 100 IMRI systems in globular clusters obtained from MOCCA simulations to their detectability. Furthermore, we model the Brownian motion IMRIs induced weak interactions with surrounding field stars include its effect on GW's phase through Doppler aberrational shift....
Abstract The opening of the gravitational wave window has significantly enhanced our capacity to explore universe's most extreme and dynamic sector. In mHz frequency range, a diverse range compact objects, from massive black holes at farthest reaches Universe lightest white dwarfs in cosmic backyard, generate complex symphony signals. Once recorded by detectors, these unique fingerprints have potential decipher birth growth structures over wide scales, stellar binaries clusters galaxies...
The velocity of a gravitational wave (GW) source provides crucial information about its formation and evolution processes. Previous studies considered the Doppler effect on phase GWs as potential signature time-dependent source. However, shift only accounts for time component vector, in principle motion also affects spatial components. latter effect, known ``aberration'' light, is analyzed this paper applied to waveform modeling an accelerating We show that additional aberrational could be...
The models currently used in the detection of gravitational waves (GWs) either do not consider a relative motion between center mass source and observer or usually only its effect on frequencies GWs. However, it is known for light that changes but also brightness source, latter which called ``beaming effect.'' We investigate such an GWs find observed amplitude GW signal, unlike behavior light, monotonic function velocity responds differently to two polarizations. attribute difference...
Most gravitational wave (GW) sources are moving relative to us. This motion is often closely related the environment of source and can thus provide crucial information about formation its host. Recently, LIGO Virgo detected for first time subdominant modes GWs. We show that a center mass affect these modes, where effect proportional velocity source. The on GW in turn affects overall frequency GW, leading phase shift. study impact this LIGO/Virgo detections it detectable with high ratios...
The opening of the gravitational wave window has significantly enhanced our capacity to explore universe's most extreme and dynamic sector. In mHz frequency range, a diverse range compact objects, from massive black holes at farthest reaches Universe lightest white dwarfs in cosmic backyard, generate complex symphony signals. Once recorded by detectors, these unique fingerprints have potential decipher birth growth structures over wide scales, stellar binaries clusters galaxies large-scale...
Standard sirens - GW sources with an EM counterpart can be used to measure H_0 directly which should help ease the existing Hubble tension. However, if source has a relative velocity expanding universe on top of its motion due flow, relativistic redshift affects and apparent distance source, thus it needs corrected obtain accurate measurements. We study effect such GWs for in showing that total wave is equal product cosmological redshift. We, further, find changes by factor (1+z_rel)^2...
Gravitational waves from a source moving relative to us can suffer special-relativistic effects such as aberration. The required velocities for these be significant are on the order of $1000\,\textrm{km s}^{-1}$. This value corresponds velocity dispersion that one finds in clusters galaxies. Hence, we expect large number gravitational-wave sources have imprinted their signals. In particular, signal will its higher modes excited, i.e., $(3,3)$ and beyond. We derive expressions describing this...
We investigate single-valued polylogarithms in two complex variables, which are relevant for the seven-point remainder function N=4 super-Yang–Mills theory multi-Regge regime. After constructing these two-dimensional polylogarithms, we determine leading logarithmic approximation of up to and including five loops.
The possibility of forming gravitational-wave sources with high center-of-mass (c.m.) velocities in the vicinity supermassive black holes requires us to develop a method deriving waveform observer's frame. Here we show that limit where c.m. velocity is but relative components source are small, can solve problem by directly integrating relaxed Einstein field equation. In particular, expand result into multipole which be conveniently calculated given orbit Our numerical calculations using...
Atom interferometry detectors like AION, ZAIGA, and AEDGE will be able to detect gravitational waves (GWs) at dHz covering the band between large space-based laser interferometers LISA/TianQin/Taiji ground-based facilities LIGO/Virgo/KAGRA. They late inspiral merger of GW sources containing intermediate-mass black holes (IMBHs) in mass range 102−105 M⊙. We study how accurately parameters an IMBH binary can measured using AION's power spectral density. Furthermore, we propose a detection...
Abstract The spherical modes of gravitational waves (GWs) have become a major focus recent detection campaigns due to the additional information they can provide about different properties source. However, GW is restricted only detecting one ray and hence it not obvious how we extract angular properties. In this note, introduce new gauge that makes visible does contain on second time derivative but also derivatives GW. particular, show are same order as wave thus allowing us constrain modes....
Space-based gravitational wave detectors like TianQin or LISA could observe extreme-mass-ratio-inspirals (EMRIs) at millihertz frequencies. The accurate identification of these EMRI signals from the data plays a crucial role in enabling in-depth study astronomy and physics. We aim stage analysis, with to extract key features signal data, such as evolution orbital frequency, well pinpoint parameter range that can fit for subsequent inference stage. In this manuscript, we demonstrate without...
With its capacity to observe $\sim 10^{5-6}$ faint active galactic nuclei (AGN) out redshift $z\approx 6$, Roman is poised reveal a population of $10^{4-6}\, {\rm M_\odot}$ black holes during an epoch vigorous galaxy assembly. By measuring the light curves subset these AGN and looking for periodicity, can identify several hundred massive hole binaries (MBHBs) with 5-12 day orbital periods, which emit copious gravitational radiation will inevitably merge on timescales $10^{3-5}$ years. During...
Space-based gravitational wave detectors like TianQin or LISA could observe extreme-mass-ratio-inspirals (EMRIs) at millihertz frequencies. The accurate identification of these EMRI signals from the data plays a crucial role in enabling in-depth study astronomy and physics. We aim stage analysis, with to extract key features signal data, such as evolution orbital frequency, well pinpoint parameter range that can fit for subsequent inference stage. In this manuscript, we demonstrated without...
Abstract Estimating the spin of Sagittarius A* (Sgr A*) is one current challenges we face in understanding center our Galaxy. In present work, show that detecting gravitational waves (GWs) emitted by a brown dwarf inspiraling around Sgr will allow us to measure mass and with unprecedented accuracy. Such systems are known as extremely large mass-ratio inspirals (XMRIs) expected be abundant loud sources Galactic center. We consider XMRIs fixed orbital inclination different spins ( s ) between...
TianQin and LISA are space-based laser interferometer gravitational wave (GW) detectors planned to be launched in the mid-2030s. Both will detect low-frequency GWs around $10^{-2}\,{\rm Hz}$, however, is more sensitive frequencies above this common sweet-spot while below Hz}$. Therefore, able same sources but with different accuracy depending on source its parameters. We consider some of most important astrophysical -- massive black hole binaries, stellar-mass double white dwarfs, extreme...
Gravitational wave (GW) detection has enabled us to test General Relativity in an entirely new regime. A prominent role tests of takes the Quasi-normal modes (QNMs) that arise as highly distorted remnant formed after merger emits GWs until it becomes a regular Kerr BH. According no-hair theorem, frequencies and damping times these QNMs are determined solely by mass spin Therefore, detecting offers unique way probe nature BH Relativity. We study merging binary black hole (BBH) intermediate...
GWnext 2024 was a meeting held in the Kavli Institute for Astronomy and Astrophysics at Peking University March $4^\text{th} - 8^\text{th}$, 2024. In researchers different career stages -- with particular focus on early scientists working aspects of gravitational wave (GW) astronomy gathered to discuss current status as well prospects field. The divided into three core sessions: Astrophysics, GW Theory, Detection. Each session consisted introductory talks extended discussion sessions....
Gravitational wave (GW) detection allows us to test general relativity in entirely new regimes. A prominent role takes the of quasi-normal modes (QNMs), which are emitted after merger a binary black hole (BBH) when highly distorted remnant emits GWs become regular Kerr (BH). The BH uniqueness theorems solutions imply that frequencies and damping times QNMs determined solely by mass spin BH. Therefore, detecting offers unique way probe nature relativity. We study merging BBH intermediate-mass...
We study the detection accuracy of double white dwarfs (DWDs), stellar-mass black hole binaries (SBHBs), light and heavy intermediate mass ratio inspirals (IMRIs), extreme (EMRIs), massive (MBHBs), stochastic gravitational wave background (SGWB) astronomical origin for TianQin, LISA, joint detection. use a Fisher matrix analysis consider each source averaged over realistic range parameters. find that on average TianQin obtains more accurate parameter estimation DWDs IMRIs, LISA EMRIs, MBHBs,...
We analyze the parameter estimation accuracy that can be achieved for mass and spin of SgrA*, SMBH in our Galactic Center, by detecting multiple extremely large mass-ratio inspirals (XMRIs). XMRIs are formed brown dwarfs (BD) inspiraling into a supermassive black hole (SMBH), thus emitting gravitational waves (GWs) inside detection band future space-based detectors such as LISA TianQin. Theoretical estimates suggest presence approximately 10 detectable GWs, making them some most promising...
Atom interferometry detectors like AION, ZAIGA, and AEDGE will be able to detect gravitational waves (GWs) at dHz covering the band between large space-based laser interferometers LISA/TianQin/Taiji ground-based facilities LIGO/Virgo/KAGRA. They late inspiral merger of GW sources containing intermediate-mass black holes (IMBHs) in mass range $10^2-10^5\,{\rm M_\odot}$. We study how accurately parameters an IMBH binary can measured using noise curve AION. Furthermore, we propose a detection...