Related papers: Probing multiple populations of compact binaries w…
The first discovery of the gravitational wave (GW) event, GW150914, suggests a higher merger rate of black-hole (BH) binaries. If this is true, a number of BH binaries will be observed via the second-generation GW detectors, and the…
Third generation gravitational-wave (GW) detectors are expected to detect a large number of binary black holes (BBHs) to large redshifts, opening up an independent probe of the large scale structure using their clustering. This probe will…
Theoretical predictions suggest that very massive stars have the potential to form through multiple collisions and eventually evolve into intermediate-mass black holes (IMBHs) within Population III star clusters embedded in mini dark matter…
We use cosmological hydrodynamic simulations to study the gravitational wave (GW) signals from high-redshift binary black holes (BBHs) formed by dynamical capture (ex-situ formation channel). We in particular focus on BHs originating from…
We propose a method for confirmation of the existence of Population III (Pop III) stars with massive black hole binaries as GW150914 in gravitational wave (GW) observation. When we get enough number of events, we want to determine which…
Previous theoretical studies suggest that the Population III (Pop3) stars tend to form in extremely metal poor gas clouds with approximately $10^5 M_\odot$ embedded in mini dark matter halos. Very massive stars can form via multiple…
We perform a binary population synthesis calculation incorporating very massive population (Pop.) III stars up to 1500 $M_\odot$, and investigate the nature of binary black hole (BBH) mergers. Above the pair-instability mass gap, we find…
Gravitational waves detected by advanced ground-based detectors have allowed studying the universe in a way which is fully complementary to electromagnetic observations. As more sources are detected, it will be possible to measure…
We investigate formation channels for merging binary black holes (BBHs) in GWTC-3, with a dedicated semiparametric population model. The model first describes or excludes a high-spin (with magnitudes of $\sim0.7$) and high-mass (ranging in…
There is increasing evidence for multiple binary black hole~(BBH) subpopulations in the cumulative gravitational wave catalog by the LIGO-Virgo-KAGRA Collaboration. The astrophysical interpretation of this complex underlying population is…
Astrophysically motivated population models for binary black hole observables are often insufficient to capture the imprints of multiple formation channels. This is mainly due to the strongly parametrized nature of such investigations.…
Population III stars, born from the primordial gas in the Universe, lose a negligible fraction of their mass via stellar winds and possibly follow a top-heavy mass function. Hence, they have often been regarded as the ideal progenitors of…
The possible existence of primordial black holes in the stellar mass window has received considerable attention because their mergers may contribute to current and future gravitational-wave detections. Primordial black hole mergers,…
Third-generation gravitational-wave detectors will observe up to millions of merging binary black holes. With such a vast dataset, stacking events into population analyses will arguably be more important than analyzing single sources. We…
The recent gravitational wave merger event, GW190521, has challenged our understanding of the stellar-mass black hole (BH) formation. The primary and secondary BH are both inferred to fall inside the pair-instability (PI) mass gap. Here we…
We study Population III (Pop III) binary remnant mergers in nuclear star clusters (NSCs) with a semi-analytical approach for early structure formation. Within this framework, we keep track of the dynamics of Pop III binary (compact object)…
The observed binary black hole (BBH) mergers indicate a large Galactic progenitor population continuously evolving from large orbital separations and low gravitational wave (GW) frequencies to the final merger phase. We investigate the…
One striking feature of binary black hole (BBH) mergers observed in the first decade of gravitational-wave astronomy is an excess of events with component masses around $35\,\mathrm{M}_{\odot}$. Multiple formation channels have been…
We introduce the first complete non-parametric model for the astrophysical distribution of the binary black hole (BBH) population. Constructed from basis splines, we use these models to conduct the most comprehensive data-driven…
The origins of coalescing binary black holes (BBHs) detected by the advanced LIGO/Virgo are still under debate, and clues may be present in the joint mass-spin distribution of these merger events. Here we construct phenomenological models…