A5078512519- Pulsars and Gravitational Waves Research
- Gamma-ray bursts and supernovae
- Astrophysical Phenomena and Observations
- Stellar, planetary, and galactic studies
- Astronomy and Astrophysical Research
- Geophysics and Gravity Measurements
- Cosmology and Gravitation Theories
- Galaxies: Formation, Evolution, Phenomena
- Astrophysics and Star Formation Studies
- High-pressure geophysics and materials
- Radio Astronomy Observations and Technology
- Geophysics and Sensor Technology
- Astro and Planetary Science
- Atomic and Subatomic Physics Research
- Relativity and Gravitational Theory
- Astrophysics and Cosmic Phenomena
- Cold Atom Physics and Bose-Einstein Condensates
- Magnetic confinement fusion research
- Black Holes and Theoretical Physics
- Seismic Waves and Analysis
- Superconducting Materials and Applications
- Astronomical Observations and Instrumentation
- Parallel Computing and Optimization Techniques
- Computational Physics and Python Applications
- Adaptive optics and wavefront sensing
University of Padua
2018-2024
Scuola Internazionale Superiore di Studi Avanzati
2020-2024
Istituto Nazionale di Fisica Nucleare, Sezione di Trieste
2020-2024
National Institute for Astrophysics
2015-2024
Astronomical Observatory of Rome
2023-2024
Istituto Nazionale di Fisica Nucleare, Sezione di Padova
2019-2024
Istituto Nazionale di Fisica Nucleare
2022-2024
University of Trieste
2020-2024
Institute for Fundamental Physics of the Universe
2022-2023
Université Paris Cité
2023
The mass spectrum of stellar black holes (BHs) is highly uncertain. Dynamical measurements are available only for few (∼10) BHs in X-ray binaries, while theoretical models strongly depend on the hydrodynamics supernova (SN) explosions and evolution massive stars. In this paper, we present discuss compact remnants that obtained with sevn, a new public population-synthesis code, which couples parsec tracks up-to-date recipes SN explosion (depending carbon–oxygen progenitor, compactness core at...
Understanding the link between massive ( 30 M ) stellar black holes (BHs) and their progenitor stars is a crucial step to interpret observations of gravitational-wave events.In this paper, we discuss final fate very (VMSs), with zero-age main sequence (ZAMS) mass >150 , accounting for pulsational pair-instability supernovae (PPISNe) (PISNe).We describe an updated version our population synthesis code SEVN, in which added evolution tracks VMSs ZAMS up 350 included analytical prescriptions...
The first four gravitational wave events detected by LIGO were all interpreted as merging black hole binaries (BHBs), opening a new perspective on the study of such systems. Here we use our population-synthesis code MOBSE, an upgraded version BSE (Hurley et al. 2002), to investigate demography BHBs. MOBSE includes metallicity-dependent prescriptions for mass loss massive hot stars. It also accounts impact electron-scattering Eddington factor loss. We perform >10^8 simulations isolated...
Searching for distinctive signatures, which characterize different formation channels of binary black holes (BBHs), is a crucial step towards the interpretation current and future gravitational wave detections. Here, we investigate demography merging BBHs in young star clusters (SCs), are nursery massive stars. We performed 4 × 103N-body simulations SCs with metallicity Z = 0.002, initial fraction 0.4, fractal conditions, to mimic clumpiness star-forming regions. Our include novel...
Studying the formation and evolution of black hole binaries (BHBs) is essential for interpretation current forthcoming gravitational wave (GW) detections. We investigate statistics BHBs that form from isolated binaries, by means a new version SEVN population-synthesis code. integrates stellar interpolation over grid tracks. upgraded to include binary processes we used it evolve sample $1.5\times{}10^8$ systems, with metallicity in range $\left[10^{-4};4\times 10^{-2}\right]$. From our...
Population-synthesis codes are an unique tool to explore the parameter space of massive binary star evolution and compact object (BCO) formation. Most population-synthesis based on same stellar model, limiting our ability main uncertainties. Here, we present new version code SEVN, which overcomes this issue by interpolating properties from a set pre-computed evolutionary tracks. We describe interpolation adaptive time-step algorithms upgrades single evolution. With evolved $1.2\times10^9$...
The cosmic merger rate density of black hole binaries (BHBs) can give us an essential clue to constraining the formation channels BHBs, in light current and forthcoming gravitational wave detections. Following a Monte Carlo approach, we couple new population-synthesis models BHBs with Illustris cosmological simulation, study history BHB mergers. We explore six models, varying prescriptions for supernovae, common envelope, natal kicks. In most considered follows same trend as star rate....
Abstract On 2019 August 14, the LIGO and Virgo detectors observed GW190814, a gravitational-wave signal originating from merger of black hole (BH) with compact object. GW190814's compact-binary source is atypical both in its highly asymmetric masses lower-mass component lying between heaviest known neutron star (NS) lightest BH compact-object binary. If formed through isolated binary evolution, mass secondary indicative at birth. We examine formation such systems evolution across suite...
Theoretical modeling of massive stars predicts a gap in the black hole (BH) mass function above $\sim 40-50\,M_{\odot}$ for BHs formed through single star evolution, arising from (pulsational) pair-instability supernovae. However, dense clusters, dynamical channels may exist that allow construction with masses excess those allowed evolution. The detection this so-called "upper-mass gap" would provide strong evidence processing prior to their eventual merger. Here, we explore detail formation...
We investigate the impact of stellar rotation on formation black holes (BHs), by means our population-synthesis code SEVN. Rotation affects mass function BHs in several ways. In massive metal-poor stars, fast reduces minimum zero-age main sequence (ZAMS) for a star to undergo pair instability and pulsational instability. Moreover, winds are enhanced rotation, peeling-off entire hydrogen envelope. As consequence these two effects, maximum BH we expect from collapse rotating is only $\sim{}45$...
Pair-instability (PI) is expected to open a gap in the mass spectrum of black holes (BHs) between $\approx{}40-65$ M$_\odot$ and $\approx{}120$ M$_\odot$. The existence currently being challenged by detection GW190521, with primary component $85^{+21}_{-14}$ M$_{\odot}$. Here, we investigate main uncertainties on PI gap: $^{12}$C($\alpha$, $\gamma$)$^{16}$O reaction rate H-rich envelope collapse. With standard rate, lower edge can be 70 if allow for collapse residual at metallicity...
ABSTRACT Pair instability (PI) and pulsational PI prevent the formation of black holes (BHs) with mass ≳60 M⊙ from single star evolution. Here, we investigate possibility that BHs in gap form via stellar mergers multiple mergers, facilitated by dynamical encounters young clusters. We analyse 104 simulations, run direct N-body code nbody6++gpu coupled population synthesis mobse. find up to ∼6 per cent all simulated have gap, depending on progenitor’s metallicity. This channel is strongly...
Young star clusters are the most common birth-place of massive stars and dynamically active environments. Here, we study formation black holes (BHs) binary (BBHs) in young clusters, by means 6000 N-body simulations coupled with population synthesis. We probe three different stellar metallicities (Z=0.02, 0.002 0.0002) two initial density regimes (density at half-mass radius $\rho_{\rm h}\ge{}3.4\times10^4$ $\ge{1.5\times10^2}$ M$_\odot$ pc$^{-3}$ dense loose respectively). Metal-poor tend to...
Characterizing the properties of host galaxies merging compact objects provides essential clues to interpret current and future gravitational-wave detections. Here, we investigate stellar mass, star formation rate (SFR), metallicity, colours in local Universe by combining results mobse population-synthesis models together with galaxy catalogues from eagle simulation. We predict that mass is an excellent tracer merger per nGW double neutron stars (DNSs), black holes (DBHs), hole–neutron...
ABSTRACT Young star clusters are likely the most common birthplace of massive stars across cosmic time and influence formation compact binaries in several ways. Here, we simulate black hole–neutron (BHNSs) young clusters, by means binary population synthesis code MOBSE interfaced with N-body NBODY6++GPU. BHNSs formed (dynamical BHNSs) significantly more than from isolated (isolated BHNSs): ∼40 per cent dynamical BHNS mergers have a total mass >15 M⊙, while only ∼0.01 excess this...
Intermediate mass black holes (IMBHs) in the range $10^2-10^5\,\mathrm{M_{\odot}}$ bridge gap between stellar (BHs) and supermassive BHs. Here, we investigate possibility that IMBHs form young star clusters via runaway collisions BH mergers. We analyze $10^4$ simulations of dense clusters, featuring up-to-date wind models prescriptions for core collapse (pulsational) pair instability. In our simulations, only 9 out 218 binary mergers, with a $\sim{}100-140$ M$_\odot$. This channel is...
On 11 February 2016, the LIGO and Virgo scientific collaborations announced first direct detection of gravitational waves, a signal caught by interferometers on 14 September 2015, produced coalescence two stellar-mass black holes. The discovery represented beginning an entirely new way to investigate Universe. latest gravitational-wave catalog LIGO, KAGRA brings total number events 90, count is expected significantly increase in next years, when additional ground-based space-born will be...
ABSTRACT We present a novel, few-body computational framework designed to shed light on the likelihood of forming intermediate-mass (IM) and supermassive (SM) black holes (BHs) in nuclear star clusters (NSCs) through successive BH mergers, initiated with single seed. Using observationally motivated NSC profiles, we find that probability an ${\sim }100\hbox{-}\mathrm{M}_\odot$ grow beyond }1000 \, \mathrm{M}_\odot$ mergers ranges from }0.1~{{\ \rm per\ cent}}$ low-density, low-mass nearly 90...
ABSTRACT The current interpretation of LIGO–Virgo–KAGRA data suggests that the primary mass function merging binary black holes (BBHs) at redshift z ≲ 1 contains multiple structures, while spins are relatively low. Theoretical models BBH formation in different environments can provide a key to interpreting population observed mergers, but they require simultaneous treatment stellar evolution and dynamics, galaxy evolution, general relativity. We present B-POP, synthesis tool model mergers...
Mergers of compact-object binaries are one the most powerful sources gravitational waves (GWs) in frequency range second-generation ground-based GW detectors (advanced LIGO and Virgo). Dynamical simulations young dense star clusters (SCs) indicate that ∼27 per cent all double members hierarchical triple systems (HTs). In this paper, we consider 570 HTs composed three compact objects (black holes or neutron stars) formed dynamically N-body SCs. We simulate them for a Hubble time with new code...
We present a set of 148 independent N-body simulations globular clusters (GCs) computed using the code CMC (Cluster Monte Carlo). At an age ∼10–13 Gyr, resulting models cover nearly full range cluster properties exhibited by Milky Way GCs, including total mass, core and half-light radii, metallicity, galactocentric distance. use our to investigate role that stellar-mass black holes play in process collapse. Furthermore, we study how dynamical interactions affect formation evolution several...
We investigate the nebular emission produced by young stellar populations using new GALSEVN model based on combination of SEVN population-synthesis code including binary-star processes and GALAXEV for spectral evolution populations. Photoionization calculations performed with CLOUDY confirm that accounting strongly influences predicted emission-line properties galaxies. In particular, we find our naturally reproduces strong HeII/Hb ratios commonly observed at high Hb equivalent widths in...
We investigate the host galaxies of compact objects merging in local Universe, by combining results binary population-synthesis simulations with Illustris cosmological box. Double neutron stars (DNSs) Universe tend to form massive (with stellar mass >109 M⊙) and merge same galaxy where they formed, a short delay time between formation progenitor DNS merger. In contrast, double black holes (DBHs) hole–neutron star binaries (BHNSs) preferentially small <1010 either or larger galaxies, long...