Collapse and nucleosynthesis of magnetized massive stars and white dwarfs

• Takami Kuroda (Max Planck Institute for Gravitational Physics)

Room: Aula Renzo Leonardi

Impact of rotation and magnetic fields on core-collapse supernovae

• Martin Obergaulinger (Universitat de València)

Room: Aula Renzo Leonardi

Magnetic Fields, Turbulence, and Vorticity in CCSN Simulations

• Carla Frohlich (North Carolina State University, United States)

Room: Aula Renzo Leonardi

Three-dimensional Core-collapse Supernova Progenitors

• Haakon Andresen (Stockholm University)

Room: Aula Renzo Leonardi Asymmetries induced by turbulent convection during late-stage stellar burning can be critical for the outcome of supernova simulations. I will present results from five three-dimensional burning simulations and discuss how the progenitor asymmetries influence the subsequent core-collapse and explosion.

Magnetized & Rotating 3D Core Collapse Supernova Progenitors

• Maria Mutz (University of Arizona)

Room: Aula Renzo Leonardi There are few three dimensional simluations exploring how magnetic fields influence pre-collapse structure and rotation in core collapse supernovae. I will present some preliminary results from a study varying magnetic field geometry in a rotating three dimensional progenitor model, discussing how they compare to previous work and what we can do with them in the future.

Magnetic fields, dissipation, and multimessenger signatures in three-dimensional core-collapse supernova simulations Room: Aula Renzo Leonardi Rapid rotation and strong magnetic fields can reshape the dynamics, energetics, and multimessenger emission of core-collapse supernovae. We investigate these effects using three-dimensional magnetohydrodynamic simulations together with hydrodynamic control models. Rotation alone modifies the protoneutron star structure, neutrino emission, post-shock dynamics, and the development of non-axisymmetric instabilities. Magnetic fields can alter this evolution further by redistributing angular momentum, extracting free energy from differential rotation, and reorganizing the flow into magnetically influenced outflows. These effects are reflected in the gravitational wave signal through rotational dynamics, protoneutron star oscillations, and large-scale asymmetries, while the neutrino signal traces changes in accretion geometry and remnant structure. Interpreting these physical and multimessenger signatures also requires understanding how magnetic energy is processed within the simulations. Energy budget diagnostics suggest that part of the extracted magnetic energy is neither retained in the resolved magnetic field nor accounted for by the resolved channels of magnetic energy conversion and transport through Lorentz work and Poynting flux, but instead appears in a dissipation-like residual. Determining whether this residual reflects unresolved reconnection, numerical diffusion, or both is important for assessing magnetic field saturation, outflow power, energy conversion efficiency, and the connection between rotational energy loss and explosion energetics. We discuss how this uncertainty may affect the physical interpretation of the overall dynamics and the multimessenger predictions of global magnetorotational supernova simulations.

Opening

• ECT* Director

Room: Aula Renzo Leonardi

Simulations of MHD CCSN Explosions

• Jennifer Quinlan (Monash University)
• Jennifer Quinlan (Monash University)

Room: Aula Renzo Leonardi

Gravitational waves from magnetorotational supernovae

• Shota Shibagaki (Wrocław University of Science and Technology)

Room: Aula Renzo Leonardi

Multimessenger Probes of Rotation in Magnetized Core-Collapse Supernovae

• Pravita Hallur (NIKHEF)

Room: Aula Renzo Leonardi

Session Q&A/transition Room: Aula Renzo Leonardi

Discussion

• Carla Frohlich (North Carolina State University, United States)
• Haakon Andresen (Stockholm University)

Room: Aula Renzo Leonardi

Overview

• Sebastiano Bernuzzi (FSU Jena)

Room: Aula Renzo Leonardi

A first-principles binary neutron star merger model of GW170817, GRB170817A, and AT2017gfo

• Kenta Kiuchi (Max Planck Institute for Gravitational Physics)

Room: Aula Renzo Leonardi

Neutrinos in neutron star merger simulations

• Francois Foucart (University of New Hampshire)

Room: Aula Renzo Leonardi I will review the role of neutrinos in neutron star mergers, the impact of individual reactions, and the current state of modeling for neutrino transport and neutrino-matter interactions.

The Role of Neutrino Transport in Delayed Collapse Binary Neutron Star Merger Remnants

• Marie Cassing (Goethe University Frankfurt)

Room: Aula Renzo Leonardi We investigate the impact of neutrino transport on delayed-collapse binary neutron-star merger remnants using general-relativistic magnetohydrodynamic (GRMHD) simulations. We compare two simulations with identical initial conditions, one employing grey, three-species M1 neutrino transport and the other neglecting neutrino radiation. Neutrino cooling advances black-hole formation and produces a cooler torus, while irradiation increases the electron fraction of the polar material. The neutrino-free model develops a larger magnetic-energy reservoir and a stronger late-time, baryon-loaded outflow. By following the evolution through collapse and into the black-hole–torus phase, we examine how neutrino cooling and irradiation influence magnetic-field amplification and the emergence of a magnetic breakout from the torus

Beyond npe matter in binary neutron star mergers

• Peter Hammond (Albert Einstein Institute)

Room: Aula Renzo Leonardi

Full-GR resistive MHD simulations of core collapse supernovae and neutron star mergers on GPUs

• Sara Azizi (University of Amsterdam)

Room: Aula Renzo Leonardi In this talk, I will present a new resistive-MHD module that I have implemented within the GPU-accelerated GRMHD code GRaM-X. This module enables fully general-relativistic resistive-MHD simulations of core-collapse supernovae and binary neutron star mergers on GPUs, using a finite-temperature microphysical equation of state and M0 neutrino transport. I will first briefly introduce the resistive-MHD implementation and present a selection of code tests used to validate the new module. I will then present results from a proof-of-concept simulation of a rapidly rotating, strongly magnetized core-collapse supernova. In this simulation, I use a finite but high electrical conductivity, and the resulting dynamics lead to the formation of a jet. Finally, I will discuss preliminary results from a second proof-of-concept simulation of a non-spinning, magnetized 1.3–1.3 \(M_\odot\) binary neutron star merger using the DD2 equation of state and the new resistive-MHD module. This part of the work is ongoing, and I will highlight some of the initial results and challenges encountered so far.

Towards Realistic Electromagnetic Counterpart Modeling of Binary Neutron Binary Mergers

• Kyohei Kawaguchi (Max-Planck-Institut für Gravitationsphysik)

Room: Aula Renzo Leonardi

Magnetic disks around prompt-collapse black holes from binary neutron star mergers

• Ricard Aguilera Miret (Hamburg Universität)

Room: Aula Renzo Leonardi

GRACE: An Open-Source Framework for GPU-Accelerated Numerical Relativity

• Carlo Musolino (Max Planck Institute for Gravitational Physics (Albert Einstein Institute))

Room: Aula Renzo Leonardi

Neural Network Emulator for M1 Neutrino Reaction Rates in Binary Neutron Star Merger

• Yi Qiu (Pennsylvania State University)

Room: Aula Renzo Leonardi We present a neural network emulator for the bns_nurates library, which computes neutrino reaction rates used in neutrino transport in binary neutron star merger simulations. We find that the emulator reproduces the opacities to within a few percents across the relevant thermodynamic conditions and accelerates their evaluation by roughly an order of magnitude. When deployed in a global \athenak binary neutron star merger simulation, it recovers the remnant structure, neutrino luminosities, and ejecta composition of a reference run using the full \nurates library, at a factor-of-two lower overall cost.

Discussion

• Albino Perego (University of Trento, Italy)
• Smaranika Banerjee (Oxford Unicersity)

Room: Aula Renzo Leonardi

Gamma rays, neutrino flavor transformation and other physics relevant for element synthesis

• Gail McLaughlin (North Carolina State University)

Room: Aula Renzo Leonardi

Telling the difference between ECSN and CCSN

• William Raphael Hix (Oak Ridge National Laboratory / Univ. of Tennessee)

Room: Aula Renzo Leonardi With ECSN, if they occur, likely being classified observationally as Type IIp, we are left in need of observable clues that will let us separate ECSN from their low mass CCSN counterparts. Details in the nucleosynthesis are likely to provide the best such clues. However, there are among the lightest CCSN, a class of ECSN mimics with which we must content. We will discuss these possibilities in the light of the results of multi-dimensional simulations for ECSN and CCSN, including the ECSN mimics.

Overview of Observational and Theoretical Constraints on Neutron Stars and the EOS

• James Lattimer (Stony Brook University)

Room: Aula Renzo Leonardi Looking back on the old Rhoades & Ruffini estimate for the neutron star maximum mass based on GR and causality, I further develop their control cheory argument to establish absolute maximum and minimum bounds to neutron star radii, moments of inertia, binding energies and tidal deformabilities as functions of central energy density (or, equivalently, mass). These bounds are compared to recent observational inferences from X-ray observations of rapidly rotating neutron stars, gravitational radiation from neutron star mergers, pulsar timing studies, and quasi-periodic oscillations seen in a few short gamma-ray busts. A new method is proposed for inferring the dense matter EOS from observations that may sharply reduce systematic biases from prior uncertainties inherent in traditional Bayesian methods that can be as large as observational uncertainties.

Impact of stellar evolution phenomena on supernova explosion and nucleosynthesis

• Luca Boccioli (TU Darmstadt)

Room: Aula Renzo Leonardi

Finite-temperature ab-initio-Informed Nuclear Equation-of-State Tables (FINEST): Nuclear matter uncertainties in core-collapse supernovae

• Finia Jost (TU Darmstadt)

Room: Aula Renzo Leonardi

Nucleosynthesis in Core-Collapse Supernova Simulations of Binary-Star Progenitors

• Gaétan Jalin (TU Darmstadt)

Room: Aula Renzo Leonardi Binary interaction is common amongst massive stars and can affect their structure and composition significantly. This has important implications for the nucleosynthetic yields and observables connecting theory and observation. However, binary- evolved progenitors remain largely unexplored in modern neutrino-driven core-collapse supernova simulations. We performed one- and two-dimensional core-collapse supernova simulations of single- and binary-star progenitors in which we investigate the impact of binary interaction on the explosion and examine the effect of in-situ networks on the dynamics and resulting nucleosynthesis relative to post-processing approaches. Our progenitors highlight the impact of binary interaction on the pre- supernova core structure of the star and its significance for explodability. In accordance with previous studies, we find that binary progenitors are generally more explodable than single stars with the same initial mass, indicating that the supernova outcome cannot be well correlated with the initial mass of the star. We find that energy generation from nuclear reactions, as well as the abundances of key isotopes such as Ni56, can be well captured by a small 𝛼-chain network. In contrast, there are notable discrepancies in the production of Ti, Cr, and Fe isotopes which remain sensitive to the network size and thermodynamic history.

Outer crust of cold, strongly magnetized neutron stars

• Juliette Servais (Université libre de Bruxelles)

Room: Aula Renzo Leonardi

Role of Fast Neutrino Flavor Conversion in Core-collapse Supernovae with the Boltzmann Neutrino Transport

• Ryuichiro Akaho (Waseda University)

Room: Aula Renzo Leonardi

Strong magnetic fields and light clusters in warm stellar matter

• Luigi Scurto (Laboratori Nazionali del Sud, INFN)

Room: Aula Renzo Leonardi

Protoneutron star asteroseismology and universality in supernova gravitational waves

• hajime sotani (Kochi University)

Room: Aula Renzo Leonardi

Session Q&A/transition Room: Aula Renzo Leonardi

Gravitational Waves from Long-Term Axisymmetric Simulations of Accretion-Induced Collapse of White Dwarfs

• Jinhao Cai (Max-Planck-Institute for Astrophysics)

Room: Aula Renzo Leonardi

Discussion Room: Aula Renzo Leonardi

Disk Outflows in Neutron Star Mergers and Collapsars

• Rodrigo Fernandez (University of Alberta)

Room: Aula Renzo Leonardi

Accretion, nucleosynthesis, dynamos and jets in mergers and extreme supernovae

• Daniel Siegel

Room: Aula Renzo Leonardi

Postmerger Disk Ejecta and Heavy Element Nucleosynthesis

• Kelsey Lund (UC Berkeley)

Room: Aula Renzo Leonardi

The Influence of Magnetic Fields and Trapped Neutrinos on the Prompt Collapse Dynamics of Neutron Star Mergers

• Raffaele Ferrari (University of Trento)

Room: Aula Renzo Leonardi

Small-scale and mean-field dynamics in accretion disks around rapidly rotating neutron stars

• Michael Müller (University of Greifswald)

Room: Aula Renzo Leonardi

Nucleosynthesis in Outflows from Neutrino-Cooled Accretion Disks Around Black Holes

• Javiera Hernández Morales (University of Greifswald)

Room: Aula Renzo Leonardi

Complex magnetic fields and nuclear EoS in extreme core-collapse supernovae

• Matteo Bugli (CEA-Saclay)

Room: Aula Renzo Leonardi

From Early Light to late Nebular Emission: Modelling Neutron Star Merger Signals

• Smaranika Banerjee (Oxford Unicersity)

Room: Aula Renzo Leonardi Overview

Binary Neutron Star Mergers with M1 Neutrino Transport: Dynamics and Ejecta

• Ruocheng Zhai (The Pennsylvania State University)

Room: Aula Renzo Leonardi

End-to-End Modeling of Kilonovae from Binary Neutron Star Mergers

• Lieke Sippens Groenewegen (Monash University)

Room: Aula Renzo Leonardi

Magnetar Imprints in Neutron Star Mergers

• Quentin Pognan (Max Planck Institute for Gravitational Physics (Albert Einstein Institute))

Room: Aula Renzo Leonardi

Discussion Room: Aula Renzo Leonardi

Hyperaccreting Neutron Stars inside Massive Envelopes

• Patrick Chi-Kit Cheong (University of New Hampshire)

Room: Aula Renzo Leonardi

r-process Nucleosynthesis and Kilonova Emission from the Induced Collapse of White Dwarfs

• Tetyana Pitik (UC Berkeley)

Room: Aula Renzo Leonardi Accretion-induced collapse (AIC) of white dwarfs provides a promising astrophysical site for r-process nucleosynthesis and kilonova emission. Drawing on results from multidimensional GRMHD and radiative transfer simulations, my talk will explore the conditions that favor robust heavy element production and discuss the electromagnetic signature of these rare and intriguing events.

Session Q&A/transition Room: Aula Renzo Leonardi

Discussion&Closeout Room: Aula Renzo Leonardi