A5020323882- Gamma-ray bursts and supernovae
- Pulsars and Gravitational Waves Research
- Astrophysics and Cosmic Phenomena
- High-Energy Particle Collisions Research
- Astrophysical Phenomena and Observations
- High-pressure geophysics and materials
- Advanced X-ray and CT Imaging
- Stellar, planetary, and galactic studies
- Magnetic confinement fusion research
- Geophysics and Gravity Measurements
- SAS software applications and methods
- Astronomy and Astrophysical Research
- Paleopathology and ancient diseases
- Nuclear Physics and Applications
- Astro and Planetary Science
Max Planck Institute for Gravitational Physics
2022-2025
University of Potsdam
2022-2025
Institute for Physics
2025
Laboratoire de Physique des 2 Infinis Irène Joliot-Curie
2023
Friedrich Schiller University Jena
2019-2021
We present a systematic numerical-relativity study of the dynamical ejecta, winds and nucleosynthesis in neutron star merger remnants. Binaries with chirp mass compatible GW170817, different ratios, five microphysical equations state (EOS) are simulated an approximate neutrino transport subgrid model for magnetohydrodynamics turbulence up to 100 milliseconds postmerger. Spiral density waves propagating from remnant disk trigger wind flux ${\sim}0.1{-}0.5\,{\rm M_\odot/s}$ persisting entire...
ABSTRACT We present new numerical relativity results of neutron star (NS) mergers with chirp mass 1.188 M⊙ and ratios q = 1.67 1.8 using finite-temperature equations state (EOS), approximate neutrino transport, a subgrid model for magnetohydrodynamics-induced turbulent viscosity. The EOS are compatible nuclear astrophysical constraints include microphysical derived from ab initio calculations based on the Brueckner–Hartree–Fock approach. report first time evidence accretion-induced prompt...
The joint detection of the gravitational wave GW170817, short $\gamma$-ray burst GRB170817A and kilonova AT2017gfo, generated by binary neutron star merger observed on August 17, 2017, is a milestone in multimessenger astronomy provides new constraints equation state. We perform Bayesian inference model selection AT2017gfo using semi-analytical, multi-components models that also account for non-spherical ejecta. Observational data favor anisotropic geometries to spherically symmetric...
(abridged) We investigate the quark deconfinement phase transition in context of binary neutron star (BNS) mergers. employ a new finite-temperature composition-dependent equation state (EOS) with first order between hadrons and deconfined quarks to perform numerical relativity simulations BNS The softening EOS due causes merger remnants be more compact collapse black hole (BH) at earlier times. is imprinted on postmerger gravitational wave (GW) signal duration, amplitude, peak frequency....
For the first $\sim3$ years after binary neutron star merger event GW 170817 radio and X-ray radiation has been dominated by emission from a structured relativistic off-axis jet propagating into low-density medium with n $< 0.01\,\rm{cm^{-3}}$. We report on observational evidence for an excess of at $\delta t>900$ days merger. With $L_x\approx5\times 10^{38}\,\rm{erg\,s^{-1}}$ 1234 days, recently detected represents $\ge 3.2\,\sigma$ (Gaussian equivalent) deviation universal post jet-break...
GRB 221009A is the brightest Gamma-Ray Burst (GRB) detected in more than 50 years of study. In this paper, we present observations X-ray and optical domains after obtained by GRANDMA Collaboration (which includes from 30 professional amateur telescopes) Insight-HXMT Collaboration. We study afterglow with empirical fitting GRANDMA+HXMT data, augmented data literature up to 60 days. then model numerically, using a Bayesian approach, HXMT-LE observations, that augment Swift-XRT additional...
A crucial ingredient in accurate simulations of neutron star-neutron star and star-black hole mergers is the inclusion neutrino transport its effects on physics astrophysics these phenomena. The authors implement a radiative scheme their general relativistic hydrodynamics code, BAM, do more accurately simulate map ejecta from mergers.
The multi-messenger detection of the gravitational-wave signal GW170817, corresponding kilonova AT2017gfo and short gamma-ray burst GRB170817A, as well observed afterglow has delivered a scientific breakthrough. For an accurate interpretation all these different messengers, one requires robust theoretical models that describe emitted gravitational-wave, electromagnetic emission, dense matter reliably. In addition, needs efficient computational tools to ensure correct cross-correlation...
Over the past three years, fading non-thermal emission from GW170817 remained generally consistent with afterglow powered by synchrotron radiation produced interaction of structured jet ambient medium. Recent observations Hajela et al. (2021) indicate change in temporal and spectral behaviour X-ray band. We show that new are compatible emergence a component due to fast tail dynamical ejecta ab-initio binary neutron star (BNS) merger simulations. This provides avenue constrain parameters....
ABSTRACT GRB 230812B is a bright and relatively nearby (z = 0.36) long gamma-ray burst (GRB) that has generated significant interest in the community thus been observed over entire electromagnetic spectrum. We report 80 observations X-ray, ultraviolet, optical, infrared, submillimetre bands from GRANDMA (Global Rapid Advanced Network for Multimessenger Addicts) network of observatories observational partners. Adding complementary data literature, we then derive essential physical parameters...
Abstract In this paper, we present PyBlastAfterglow, a modular C++ code with Python interface to model light curves and sky maps of gamma-ray burst afterglows. The is open-source, modular, sufficiently fast perform parameter grid studies. PyBlastAfterglow designed be easily extendable used as testing bed for new physics methods related For the dynamical evolution relativistic ejecta, thin-shell approximation adopted, where both forward reverse shocks are included self-consistently, well...
Given an increasing number of gamma-ray bursts accompanied by potential kilonovae there is a growing importance to advance modelling kilonova afterglows. In this work, we investigate how the presence two electron populations that follow Maxwellian (thermal) and power-law (non-thermal) distributions affect afterglow light curves. We employ semi-analytic model, $\texttt{PyBlastAfterglow}$. consider ejecta profiles from ab-initio numerical relativity binary neutron star merger simulations,...
ABSTRACT Although GRB 211211A is one of the closest gamma-ray bursts (GRBs), its classification challenging because partially inconclusive electromagnetic signatures. In this paper, we investigate four astrophysical scenarios as possible progenitors for 211211A: a binary neutron star merger, black hole–neutron core-collapse supernova, and an r-process enriched core collapse rapidly rotating massive (a collapsar). We perform large set Bayesian multiwavelength analyses based on different...
The AT2017gfo kilonova counterpart of the binary neutron star merger event GW170817 was characterized by an early-time bright peak in optical and UV bands. Such blue is commonly interpreted as a signature weak $r$-process nucleosynthesis fast expanding wind whose origin currently debated. Numerical-relativity simulations with microphysical equations state, approximate neutrino transport, turbulent viscosity reveal new mechanism that can power kilonova. Spiral density waves remnant generate...
ABSTRACT In this paper, we compute and analyse synthetic radio images of gamma-ray bursts (GRBs) kilonova afterglows. For modelling the former, consider GRB170817A-inspired set parameters, while for latter, employ ejecta profiles from numerical-relativity simulations. We find that afterglow sky map has a doughnut-like structure at early times becomes more ring-like late times. This is caused by fact synchrotron emission electrons following Maxwellian distribution function dominates beamed...
Neutrino interactions are essential for an accurate understanding of the binary neutron star merger process. In this article, we extend code infrastructure well-established numerical-relativity BAM that until recently neglected neutrino-driven interactions. fact, while previous work allowed already usage nuclear-tabulated equations state and employing a neutrino leakage scheme, moving forward by implementing first-order multipolar radiation transport scheme (M1) advection neutrinos. After...
GW170817 and its associated electromagnetic counterpart AT2017gfo continue to be a treasure trove as observations modeling continue. Recent precision astrometry of with the Hubble Space Telescope combined previous constraints from Very Long Baseline Interferometry (VLBI) narrowed down inclination angle 19-25 deg (90\% confidence). This paper explores how inclusion precise information can reveal new insights about ejecta properties, in particular, composition dynamical AT2017gfo. Our analysis...
We present fitting formulae for the dynamical ejecta properties and remnant disk masses from largest to date sample of numerical relativity simulations. The considered data include some latest simulations with microphysical nuclear equations state (EOS) neutrino transport as well other results polytropic EOS available in literature. Our analysis indicates that broad features can be captured by expressions depend on mass ratio reduced tidal parameter. comparative literature shows microphysics...
In this paper, we compute and analyze synthetic radio images of gamma-ray bursts kilonova afterglows. For modeling the former, consider GRB170817A-inspired set parameters, while for latter, employ ejecta profiles from numerical-relativity simulations. We find that afterglow sky map has a doughnut-like structure at early times becomes more ring-like late times. This is caused by fact synchrotron emission electrons following Maxwellian distribution function dominates early, beamed, emissions...
GRB~230812B is a bright and relatively nearby ($z =0.36$) long gamma-ray burst (GRB) that has generated significant interest in the community thus been observed over entire electromagnetic spectrum. We report 80 observations X-ray, ultraviolet, optical, infrared, sub-millimeter bands from GRANDMA (Global Rapid Advanced Network for Multi-messenger Addicts) network of observatories observational partners. Adding complementary data literature, we then derive essential physical parameters...
Although GRB 211211A is one of the closest gamma-ray bursts (GRBs), its classification challenging because partially inconclusive electromagnetic signatures. In this paper, we investigate four different astrophysical scenarios as possible progenitors for GRB~211211A: a binary neutron-star merger, black-hole--neutron-star core-collapse supernova, and an r-process enriched core collapse rapidly rotating massive star (a collapsar). We perform large set Bayesian multi-wavelength analyses based...