A5040504061- Gamma-ray bursts and supernovae
- Pulsars and Gravitational Waves Research
- Astrophysical Phenomena and Observations
- Solar and Space Plasma Dynamics
- High-pressure geophysics and materials
- Fluid Dynamics and Turbulent Flows
- Cosmology and Gravitation Theories
- Magnetic confinement fusion research
Universität Hamburg
2023-2024
Universitat de les Illes Balears
2019-2023
Institut d'Estudis Espacials de Catalunya
2019-2022
Magnetic fields are expected to play a key role in the dynamics and ejection mechanisms that accompany merger of two neutron stars. General relativistic magnetohydrodynamic (MHD) simulations offer unique opportunity unravel details ongoing physical processes. Nevertheless, current numerical studies severely limited by fact any affordable resolution remains insufficient fully capture small-scale dynamo, initially triggered Kelvin-Helmholtz instability, later sourced several MHD processes...
We have conducted fully relativistic simulations in a class of scalar-tensor theories with derivative self-interactions and screening local scales. By using high-resolution shock-capturing methods nonvanishing shift vector, we managed to avoid issues plaguing similar attempts the past. first confirmed recent results by ourselves spherical symmetry, obtained an approximate approach pointing at partial breakdown black-hole collapse. Then, considered late inspiral merger binary neutron stars....
We perform a long and accurate large-eddy simulation of binary neutron star merger, following the newly formed remnant up to 110 milliseconds. The combination high-order schemes, high-resolution, gradient subgrid-scale model allows us have among highest effective resolutions ever achieved. Our results show that, although magnetic fields are strongly amplified by Kelvin-Helmholtz instability, they coherent only over very short spatial scales until $t\ensuremath{\gtrsim}30\text{ }\text{...
The detection of a binary neutron star merger in 2017 through both gravitational waves and electromagnetic emission opened new era multimessenger astronomy. understanding the magnetic field amplification triggered by Kelvin-Helmholtz instability during is still numerically unresolved problem because relevant small scales involved. One uncertainties comes from simplifications usually assumed initial topology merging stars. We perform high-resolution, convergent large-eddy simulations mergers,...
The detection of binary neutron star mergers represents one the most important and complex astrophysical discoveries recent years. One unclear aspects problem is turbulent magnetic field amplification, initially triggered by Kelvin-Helmholtz instability at much smaller scales than any reachable numerical resolution nowadays. Here we present simulations first 10 milliseconds a merger. First, confirm in detail how simulated amplification depends on distributed broad range scales, as expected...
In several relativistic astrophysics scenarios, the understanding of rich magnetohydrodynamics is hampered by limitations set achievable numerical resolution. these cases, it a tremendous challenge to accurately simulate numerically all relevant scales. We present how study such systems using large eddy simulations with self-consistent subgrid-scale gradient model that we generalized special case in previous work and now extend general case. Adapted from nonrelativistic so-called allows us...
Performing accurate large eddy simulations in compressible, turbulent magnetohydrodynamics (MHDs) is more challenging than nonmagnetized fluids due to the complex interplay between kinetic, magnetic, and internal energy at different scales. Here, we extend subgrid-scale gradient model, so far used momentum induction equations, also account for unresolved scales evolution equation of a compressible ideal MHD fluid with generic state. We assess model by considering box turbulence triggered...
We perform a long and accurate Large-Eddy Simulation of binary neutron star merger, following the newly formed remnant up to 110 milliseconds. The combination high-order schemes, high-resolution gradient subgrid-scale model allow us have among highest effective resolutions ever achieved. Our results show that, although magnetic fields are strongly amplified by Kelvin-Helmholtz instability, they coherent only over very short spatial scales until t \gtrsim 30 ms. Around that time, winding...
We analyze a long-lived hyper-massive neutron star merger remnant (post-merger lifetime $>250$ ms) that has been obtained via large eddy simulations with gradient subgrid-scale model. find clear helicoidal magnetic field structure is governed by the toroidal component of field. Although no jet emerges during simulation time, we observe at late times significant increase poloidal all scales. also compare results several binary moderate resolution $120$~m, are evolved up to $50$~ms after...