Publications (64)
Energy Dissipation in Interstellar Cloud Collisions
Massimo Ricotti, Andrea Ferrara, Francesco Miniati
We present a study of the kinetic energy dissipation in interstellar cloud collisions. The main aim is to understand the dependence of the elasticity (defined as the ratio of the f…
Strong magnetic fields in normal galaxies at high redshifts
Martin L. Bernet, Francesco Miniati, Simon J. Lilly +2
The origin and growth of magnetic fields in galaxies is still something of an enigma. It is generally assumed that seed fields are amplified over time through the dynamo effect, bu…
Signatures of Magnetized Large Scale Structure in Ultra-High Energy Cosmic Rays
Guenter Sigl, Francesco Miniati, Torsten Ensslin
We investigate the impact of a structured universe in the multi-pole moments, auto-correlation function, and cluster statistics of cosmic rays above 10^19 eV. We compare structured…
Glimm-Godunov's Method for Cosmic-ray-hydrodynamics
Francesco Miniati
A numerical method for integrating the equations describing a dynamically coupled system made of a fluid and cosmic-rays is developed. In smooth flows the effect of CR pressure is…
Properties of Cosmic Shock Waves in Large Scale Structure Formation
Francesco Miniati, Dongsu Ryu, Hyesung Kang +3
We have examined the properties of shock waves in simulations of large scale structure formation for two cosmological scenarios (a SCDM and a LCDM with Omega =1). Large-scale shock…
Learning Heat Transport Kernels Using a Nonlocal Heat Transport Theory-Informed Neural Network
Mufei Luo, Charles Heaton, Yizhen Wang +5
We present a data-driven framework for the modeling of nonlocal heat transport in plasmas using a nonlocal theory informed neural network trained on kinetic Particle-in-Cell simula…
Inter-galactic Shock Acceleration and the Cosmic Gamma-ray Background
Francesco Miniati
We investigate numerically the contribution to the cosmic gamma-ray background from cosmic-rays ions and electrons accelerated at intergalactic shocks associated with cosmological…
Cosmic Ray Protons Accelerated at Cosmological Shocks and Their Impact on Groups and Clusters of Galaxies
Francesco Miniati, Dongsu Ryu, Hyesung Kang +1
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 inc…
Ultra-High Energy Cosmic Ray Probes of Large Scale Structure and Magnetic Fields
Guenter Sigl, Francesco Miniati, Torsten Ensslin
We study signatures of a structured universe in the multi-pole moments, auto-correlation function, and cluster statistics of ultra-high energy cosmic rays above 10^19 eV. We compar…
Primordial magnetic field constraints from the end of reionization
Dominik R. G. Schleicher, Francesco Miniati
Primordial magnetic fields generated in the early universe are subject of considerable investigation, and observational limits on their strength are required to constrain the theor…
Cosmic ray transport in galaxy clusters: implications for radio halos, gamma-ray signatures, and cool core heating
Torsten A. Ensslin, Christoph Pfrommer, Francesco Miniati +1
We investigate the interplay of cosmic ray (CR) propagation and advection in galaxy clusters. Propagation in form of CR diffusion and streaming tends to drive the CR radial profile…
COSMOCR: A Numerical Code for Cosmic Ray Studies in Computational Cosmology
Francesco Miniati
We present COSMOCR, a numerical code for the investigation of cosmic ray related studies in computational cosmology. The code follows the diffusive shock acceleration, the mechanic…
Ultrahigh energy cosmic rays as heavy nuclei from cluster accretion shocks
Susumu Inoue, Guenter Sigl, Francesco Miniati +1
Large-scale accretion shocks around massive clusters of galaxies, generically expected in the cold dark matter scenario of cosmological structure formation, are shown to be plausib…
Axion driven cosmic magneto-genesis during the QCD crossover
Francesco Miniati, Gianluca Gregori, Brian Reville +1
We propose a mechanism for the generation of a magnetic field in the early universe during the QCD crossover assuming that dark matter is made of axions. Thermoelectric fields aris…
Enhanced Cloud Disruption by Magnetic Field Interaction
G. Gregori, Francesco Miniati, Dongsu Ryu +1
We present results from the first three-dimensional numerical simulations of moderately supersonic cloud motion through a tenuous, magnetized medium. We show that the interaction o…
Winds and Shocks in Galaxy Clusters: Shock Acceleration on an Intergalactic Scale
T. W. Jones, Francesco Miniati, Dongsu Ryu +1
We review the possible roles of large scale shocks as particle accelerators in clusters of galaxies. Recent observational and theoretical work has suggested that high energy charge…
Ultrahigh energy cosmic rays as heavy nuclei from cluster accretion shocks
Susumu Inoue, Guenter Sigl, Francesco Miniati +1
Large-scale accretion shocks around massive clusters of galaxies, generically expected in hierarchical scenarios of cosmological structure formation, are shown to be potential sour…
Extreme Cosmic-Ray-Dominated-Regions: a new paradigm for high star formation density events in the Universe
Padeli P. Papadopoulos, Wing-Fai Thi, Francesco Miniati +1
We examine in detail the recent proposal that extreme Cosmic-Ray-Dominated-Regions (CRDRs) characterize the ISM of galaxies during events of high-density star formation, fundamenta…
Turbulent Amplification and Structure of the Intracluster Magnetic Field
Andrey Beresnyak, Francesco Miniati
We compare DNS calculations of homogeneous isotropic turbulence with the statistical properties of intra-cluster turbulence from the Matryoshka Run (Miniati 2014) and find remarkab…
Angular Anisotropies in the Cosmic Gamma-ray Background as a Probe of its Origin
Francesco Miniati, Savvas M. Koushiappas, Tiziana Di Matteo
Notwithstanding the advent of the Gamma-ray Large Area Telescope, theoretical models predict that a significant fraction of the cosmic gamma-ray background (CGB), at the level of 2…
Cosmic Rays and Their Radiative Processes in Numerical Cosmology
Dongsu Ryu, Francesco Miniati, Tom W. Jones +1
A cosmological hydrodynamic code is described, which includes a routine to compute cosmic ray acceleration and transport in a simplified way. The routine was designed to follow exp…
The Matryoshka Run (II): Time Dependent Turbulence Statistics, Stochastic Particle Acceleration and Microphysics Impact in a Massive Galaxy Cluster
Francesco Miniati
We use the Matryoshka run to study the time dependent statistics of structure-formation driven turbulence in the intracluster medium of a 10 galaxy cluster. We invest…
Faraday Rotation Measure Synthesis of intermediate redshift quasars as a probe of intervening matter
Kwang Seong Kim, Simon J. Lilly, Francesco Miniati +4
There is evidence that magnetized material along the line of sight to distant quasars is detectable in the polarization properties of the background sources. The polarization prope…
Magnetic fields in the first galaxies: Dynamo amplification and limits from reionization
Dominik R. G. Schleicher, Jennifer Schober, Christoph Federrath +3
We discuss the amplification of magnetic fields by the small-scale dynamo, a process that could efficiently produce strong magnetic fields in the first galaxies. In addition, we de…
A numerical model of resistive generation of intergalactic magnetic field at cosmic dawn
Francesco Miniati, A. R. Bell
Miniati and Bell (2011) proposed a mechanism for the generation of magnetic seeds that is based the finite resistivity of the low temperature IGM in the high redshift universe. In…
3-D MHD Numerical Simulations of Cloud-Wind Interactions
G. Gregori, Francesco Miniati, Dongsu Ryu +1
We present results from three-dimensional (3-D) numerical simulations investigating the magnetohydrodynamics of cloud-wind interactions. The initial cloud is spherical while the ma…
Self-similar energetics in large clusters of galaxies
Francesco Miniati, Andrey Beresnyak
Massive galaxy clusters are filled with a hot, turbulent and magnetized intra-cluster medium. Still forming under the action of gravitational instability, they grow in mass by accr…
Block Structured Adaptive Mesh and Time Refinement for Hybrid, Hyperbolic + N-body Systems
Francesco Miniati, Phillip Colella
We present a new numerical algorithm for the solution of coupled collisional and collisionless systems, based on the block structured adaptive mesh and time refinement strategy (AM…
Gamma-rays from the Large Scale Structure of the Universe
Francesco Miniati
Gamma-ray astronomy will play a crucial role in the investigation of nonthermal processes in the large scale structure of the universe. Particularly, galaxy clusters (GC) observati…
Fluorescent Ly-alpha emission from the high-redshift intergalactic medium
Sebastiano Cantalupo, Cristiano Porciani, Simon J. Lilly +1
We combine a high-resolution hydro-simulation of the LambdaCDM cosmology with two radiative transfer schemes (for continuum and line radiation) to predict the properties, spectra a…
Numerical Modeling of Gamma Radiation from Galaxy Clusters
Francesco Miniati
We investigate the spatial and spectral properties of non-thermal emission from clusters of galaxies at gamma-ray energies between 10 keV and 10 TeV due to inverse-Compton (IC) emi…
Ultraviolet Background Radiation from Cosmic Structure Formation
Francesco Miniati, Andrea Ferrara, Simon D. M. White +1
We calculate the contribution to the ultraviolet background (UVB) from thermal emission from gas shock heated by cosmic structure formation. Our main calculation is based on an upd…
Acceleration of CR at Large Scale Shocks and Their Cosmological Role for Structure Formation in the Universe
Francesco Miniati, Dongsu Ryu, T. W. Jones +1
We investigate the dynamical importance of a newly recognized possible source of significant feedback generated during structure formation; namely cosmic ray (CR) pressure. We pres…
Deeper Chandra Follow-up of Cygnus TeV Source Perpetuates Mystery
Yousaf Butt, Jeremy Drake, Paula Benaglia +4
A 50 ksec Chandra observation of the unidentified TeV source in Cygnus reported by the HEGRA collaboration reveals no obvious diffuse X-ray counterpart. However, 240 Pointlike X-ra…
Cosmic ray transport in galaxy clusters: implications for radio halos and gamma-rays
Christoph Pfrommer, Torsten Ensslin, Francesco Miniati +1
Observations of giant radio halos provide unambiguous evidence for the existence of cosmic ray (CR) electrons and magnetic fields in galaxy clusters. The physical mechanism generat…
On the Exchange of Kinetic and Magnetic Energy Between Clouds and the Interstellar Medium
Francesco Miniati, T. W. Jones, Dongsu Ryu
We investigate, through 2D MHD numerical simulations, the interaction of a uniform magnetic field oblique to a moving interstellar cloud. In particular we explore the transformatio…
Evidence for Shock Acceleration and Intergalactic Magnetic Fields in a Large-Scale Filament of Galaxies ZwCl 2341.1+0000
Joydeep Bagchi, Torsten A. Ensslin, Francesco Miniati +4
We report the discovery of large-scale diffuse radio emission from what appears to be a large-scale filamentary network of galaxies in the region of cluster ZwCl 2341.1+0000, and s…
Gamma Ray Astronomy with Magnetized Zevatrons
Eric Armengaud, Guenter Sigl, Francesco Miniati
Nearby sources of cosmic rays up to a ZeV(=10^21 eV) could be observed with a multi-messenger approach including secondary gamma-rays and neutrinos. If cosmic rays above ~10^18 eV…
Constrained-Transport Magnetohydrodynamics with Adaptive-Mesh-Refinement in CHARM
Francesco Miniati, Daniel F. Martin
We present the implementation of a three-dimensional, second order accurate Godunov-type algorithm for magneto-hydrodynamic (MHD), in the adaptive-mesh-refinement (AMR) cosmologica…
Ultra-High Energy Cosmic Rays in a Structured and Magnetized Universe
Guenter Sigl, Francesco Miniati, Torsten Ensslin
We simulate propagation of cosmic ray nucleons above 10^{19} eV in scenarios where both the source distribution and magnetic fields within about 50 Mpc from us are obtained from an…
Suppression of pair beam instabilities in a laboratory analogue of blazar pair cascades
Charles D. Arrowsmith, Francesco Miniati, Pablo J. Bilbao +28
The generation of dense electron-positron pair beams in the laboratory can enable direct tests of theoretical models of -ray bursts and active galactic nuclei. We have successf…
Investigating Galaxy Clusters through Gamma-ray Emission
Francesco Miniati
We address the role of gamma-ray astronomy in the investigation of nonthermal processes in the large scale structure of the universe. Based on EGRET upper limits on nearby galaxy c…
Learning Transport Processes with Machine Intelligence
Francesco Miniati, Gianluca Gregori
We present a machine learning based approach to address the study of transport processes, ubiquitous in continuous mechanics, with particular attention to those phenomena ruled by…
A Hybrid Scheme for Gas-Dust Systems Stiffly Coupled via Viscous Drag
Francesco Miniati
We present a stable and convergent method for studying a system of gas and dust, coupled through viscous drag in both non-stiff and stiff regimes. To account for the effects of dus…
Large Cosmic Shock Waves as Sites for Particle Acceleration
Francesco Miniati, Dongsu Ryu, Hyesung Kang +1
The properties of cosmic shock waves are studied through numerical simulations in two cosmological scenarios (SCDM and LCDM). The scaling relations for the average radius and veloc…
CHANDRA/VLA Follow-up of TeV J2032+4131, the Only Unidentified TeV Gamma-ray Source
Yousaf Butt, Paula Benaglia, Jorge Combi +10
The HEGRA Cherenkov telescope array group recently reported a steady and extended unidentified TeV gamma-ray source lying at the outskirts of Cygnus OB2. This is the most massive s…
Ultrahigh Energy Nuclei Propagation in a Structured, Magnetized Universe
Eric Armengaud, Guenter Sigl, Francesco Miniati
We compare the propagation of iron and proton nuclei above 10^19 eV in a structured Universe with source and magnetic field distributions obtained from a large scale structure simu…
Magnetohydrodynamics of Cloud Collisions in a Multi-phase Interstellar Medium
Francesco Miniati, Dongsu Ryu, Andrea Ferrara +1
We extend previous studies of the physics of interstellar cloud collisions by beginning investigation of the role of magnetic fields through 2D magnetohydrodynamic (MHD) numerical…
Structure Shocks as a Source of Cosmic Rays in Clusters
T. W. Jones, Francesco Miniati, Dongsu Ryu +2
Shocks are a ubiquitous consequence of cosmic structure formation, and they play an essential role in heating galaxy cluster media. Virtually all of the gas in clusters has been pr…
Relaxation of Blazar Induced Pair Beams in Cosmic Voids
Francesco Miniati, Andrii Elyiv
The stability properties of a low density ultra relativistic pair beam produced in the intergalactic medium by multi-TeV gamma-ray photons from blazars are analyzed. The problem is…
Cosmic Ray Acceleration by Stellar Associations? The Case of Cygnus OB2
Yousaf Butt, Paula Benaglia, Jorge Combi +10
The origins of all extra-solar cosmic rays -- both the ultra high-energy and lower energy Galactic variety -- remain unclear. It has been argued that the large scale shocks and tur…
The 21 centimeter emission from the reionization epoch: extended and point source foregrounds
Tiziana Di Matteo, Benedetta Ciardi, Francesco Miniati
Fluctuations in the redshifted 21 centimeter emission from neutral hydrogen probe the epoch of reionization. We examine the observability of this signal and the impact of extragala…
The X-Ray Zurich Environmental Study (X-ZENS). II. X-ray Observations of the Diffuse Intragroup Medium in Galaxy Groups
Francesco Miniati, Alexis Finoguenov, John D. Silverman +4
We present the results of a pilot XMM- and program aimed at studying the diffuse intragroup medium (DIM) of optically-selected nearby groups from the Zurinch ENvi…
Fundamental differences between SPH and grid methods
Oscar Agertz, Ben Moore, Joachim Stadel +17
We have carried out a hydrodynamical code comparison study of interacting multiphase fluids. The two commonly used techniques of grid and smoothed particle hydrodynamics (SPH) show…
The survival of interstellar clouds against Kelvin-Helmholtz instabilities
Mario Vietri, Andrea Ferrara, Francesco Miniati
We consider the stability of clouds surrounded by a hotter confining medium with respect to which they are in motion, against Kelvin-Helmholtz instabilities (KHI). In the presence…
Cosmic Magnetic Fields and Their Influence on Ultra-High Energy Cosmic Ray Propagation
Guenter Sigl, Francesco Miniati, Torsten Ensslin
We discuss the influence of large scale cosmic magnetic fields on the propagation of hadronic cosmic rays above 10^19 eV based on large scale structure simulations. Our simulations…
Time-Embedded Convolutional Neural Networks for Modeling Plasma Heat Transport
Mufei Luo, Charles Heaton, Yizhen Wang +5
We introduce a time-embedded convolutional neural network (TCNN) for modeling spatiotemporal heat transport in plasmas, particularly under strongly nonlocal conditions. In our earl…
The Matryoshka Run: Eulerian Refinement Strategy to Study Statistics of Turbulence in Virialized Cosmic Structures
Francesco Miniati
We study the statistical properties of turbulence driven by structure formation in a massive merging galaxy cluster at z=0. The development of turbulence is ensured as the largest…
A Modified Higher Order Godunov's Scheme for Stiff Source Conservative Hydrodynamics
Francesco Miniati, Phillip Colella
Hyperbolic conservation laws with stiff source terms appear in the study of a variety of physical systems. Early work showed that the use of formally second-order accurate semi-imp…
Cosmic Ray Electrons in Groups and Clusters of Galaxies: Primary and Secondary Populations from a Numerical Cosmological Simulation
Francesco Miniati, T. W. Jones, Hyesung Kang +1
We study the generation and distribution of high energy electrons in cosmic environment and their observational consequences by carrying out the first cosmological simulation that…
Hydrodynamics of Cloud Collisions in 2D: The Fate of Clouds in a Multi-phase Medium
Francesco Miniati, T. W. Jones, Andrea Ferrara +1
We have studied head-on collisions between equal-mass, mildly supersonic (Mach number 1.5) HI clouds, in a standard Two-phase ISM (T_cl = 74 K, n_cl = 22 cm^-3, Ï= 100). We explor…
A Divergence-Free Upwind Code for Multidimensional Magnetohydrodynamic Flows
Dongsu Ryu, Francesco Miniati, T. W. Jones +1
A description is given for preserving ${\bmsy\nabla}\cdot{\vec B}=0$ in a magnetohydrodynamic (MHD) code that employs the upwind, Total Variation Diminishing (TVD) scheme and the S…
Resistive Magnetic Field Generation at Cosmic Dawn
Francesco Miniati, A. R. Bell
Relativistic charged particles (CR for cosmic-rays) produced by Supernova explosion of the first generation of massive stars that are responsible for the re-ionization of the unive…
Inverse Compton gamma-rays from Galactic dark matter annihilation: Anisotropy signatures
Le Zhang, Francesco Miniati, Guenter Sigl
High energy electrons and positrons from annihilating dark matter can imprint unique angular anisotropies on the diffuse gamma-ray flux by inverse Compton scattering off the inters…