English
Related papers

Related papers: Comparing energy and entropy formulations for cosm…

200 papers

We present cosmological hydrodynamical simulations of eight Milky Way-sized haloes that have been previously studied with dark matter only in the Aquarius project. For the first time, we employ the moving-mesh code AREPO in zoom simulations…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-16 Federico Marinacci , Ruediger Pakmor , Volker Springel

We investigate the production of cosmic ray (CR) protons at cosmological shocks by performing, for the first time, numerical simulations of large scale structure formation that include directly the acceleration, transport and energy losses…

Astrophysics · Physics 2009-11-06 Francesco Miniati , Dongsu Ryu , Hyesung Kang , T. W. Jones

The energy densities in magnetic fields and cosmic rays (CRs) in galaxies are often assumed to be in equipartition, allowing for an indirect estimate of the magnetic field strength from the observed radio synchrotron spectrum. However, both…

Astrophysics of Galaxies · Physics 2016-01-27 Tova M. Yoast-Hull , John S. Gallagher , Ellen G. Zweibel

We present two numerical schemes for passive tracer particles in the hydrodynamical moving-mesh code AREPO, and compare their performance for various problems, from simple setups to cosmological simulations. The purpose of tracer particles…

Instrumentation and Methods for Astrophysics · Physics 2013-08-20 Shy Genel , Mark Vogelsberger , Dylan Nelson , Debora Sijacki , Volker Springel , Lars Hernquist

A new cosmological multidimensional hydrodynamic and N-body code based on an Adaptive Mesh Refinement scheme is described and tested. The hydro part is based on modern high-resolution shock-capturing techniques, whereas N-body approach is…

Astrophysics · Physics 2009-11-10 Vicent Quilis

We test and improve the numerical schemes in our smoothed particle hydrodynamics (SPH) code for cosmological simulations, including the pressure-entropy formulation (PESPH), a time-dependent artificial viscosity, a refined timestep…

Galactic cosmic rays (CRs) are accelerated by astrophysical shocks, primarily supernova remnants (SNRs), via diffusive shock acceleration (DSA), an efficient mechanism that predicts power-law energy distributions of CRs. However,…

High Energy Astrophysical Phenomena · Physics 2021-09-24 Rebecca Diesing , Damiano Caprioli

Non-relativistic shocks accelerate ions to highly relativistic energies provided that the orientation of the magnetic field is closely aligned with the shock normal (quasi-parallel shock configuration). In contrast, quasi-perpendicular…

High Energy Astrophysical Phenomena · Physics 2018-06-13 M. Pais , C. Pfrommer , K. Ehlert , R. Pakmor

Cosmic rays (CRs) are a pivotal non-thermal component of galaxy formation and evolution. However, the intricacies of CR physics, particularly how they propagate in the circumgalactic medium (CGM), remain largely unconstrained. In this work,…

We study the propagation of mildly-relativistic cosmic rays (CRs) in multiphase interstellar medium environments with conditions typical of nearby disk galaxies. We employ the techniques developed in Armillotta+21 to post-process three…

Astrophysics of Galaxies · Physics 2022-05-04 Lucia Armillotta , Eve C. Ostriker , Yan-Fei Jiang

We present new results characterizing cosmological shocks within adaptive mesh refinement N-Body/hydrodynamic simulations that are used to predict non-thermal components of large-scale structure. This represents the first study of shocks…

We calculate spectra of escaping cosmic rays (CRs) accelerated at shocks produced by expanding Galactic superbubbles powered by multiple supernovae producing a continuous energy outflow in star-forming galaxies. We solve the generalized…

High Energy Astrophysical Phenomena · Physics 2020-01-28 Zhaowei Zhang , Kohta Murase , Peter Mészáros

The common envelope (CE) phase is an important stage in binary stellar evolution. It is needed to explain many close binary stellar systems, such as cataclysmic variables, Type Ia supernova progenitors, or X-ray binaries. To form the…

Solar and Stellar Astrophysics · Physics 2016-01-13 Sebastian T. Ohlmann , Friedrich K. Roepke , Ruediger Pakmor , Volker Springel

High precision spectrometry of galactic cosmic rays (CR) has revealed the lack of our understanding of how different CR elements are extracted from the supernova environments to be further accelerated in their shocks. Comparing the spectra…

High Energy Astrophysical Phenomena · Physics 2017-07-11 Adrian Hanusch , Tatyana Liseykina , Mikhail Malkov

Heating of virialized gas by streaming cosmic rays (CRs) may be energetically important in galaxy halos, groups and clusters. We present a linear thermal stability analysis of plasmas heated by streaming CRs. We separately treat equilibria…

Astrophysics of Galaxies · Physics 2020-02-24 Philipp Kempski , Eliot Quataert

Compact Runge-Kutta (cRK) methods are a class of high order methods for solving hyperbolic conservation laws characterized by their compact stencil including only immediate neighboring finite elements. A Compact Runge-Kutta flux…

Numerical Analysis · Mathematics 2026-04-03 Arpit Babbar , Qifan Chen , Hendrik Ranocha

Hydrodynamic simulations have become irreplaceable in modern cosmology for exploring complex systems and making predictions to steer future observations. In Chapter 1, we begin with a philosophical discussion on the role of simulations in…

Cosmology and Nongalactic Astrophysics · Physics 2023-12-20 Edoardo Altamura

We describe a systematic development of kinetic entropy as a diagnostic in fully kinetic particle-in-cell (PIC) simulations and use it to interpret plasma physics processes in heliospheric, planetary, and astrophysical systems. First, we…

A recent paper by Lucas-Serrano et al. indicates that a high-resolution central (HRC) scheme is robust enough to yield accurate hydrodynamical simulations of special relativistic flows in the presence of ultrarelativistic speeds and strong…

General Relativity and Quantum Cosmology · Physics 2009-11-11 Masaru Shibata , José A. Font

The key aspect determining the post-formation luminosity of gas giants has long been considered to be the energetics of the accretion shock at the planetary surface. We use 1D radiation-hydrodynamical simulations to study the radiative loss…

Earth and Planetary Astrophysics · Physics 2017-03-08 Gabriel-Dominique Marleau , Hubert Klahr , Rolf Kuiper , Christoph Mordasini