A5058717341- Galaxies: Formation, Evolution, Phenomena
- Astrophysics and Cosmic Phenomena
- Radio Astronomy Observations and Technology
- Computational Physics and Python Applications
- Distributed and Parallel Computing Systems
- Advanced Data Storage Technologies
- Astronomical Observations and Instrumentation
- Astrophysics and Star Formation Studies
- Astronomy and Astrophysical Research
- Scientific Computing and Data Management
- Cosmology and Gravitation Theories
- Solar and Space Plasma Dynamics
- Scientific Research and Discoveries
- Computer Graphics and Visualization Techniques
- Advanced Computational Techniques and Applications
- Gamma-ray bursts and supernovae
- Magnetic confinement fusion research
- Geophysics and Gravity Measurements
- Stellar, planetary, and galactic studies
- Parallel Computing and Optimization Techniques
- Particle Detector Development and Performance
- Particle accelerators and beam dynamics
- Data Visualization and Analytics
- Ionosphere and magnetosphere dynamics
- Dark Matter and Cosmic Phenomena
National Institute for Astrophysics
2021-2024
Istituto di Radioastronomia di Bologna
2020-2024
CSCS - Swiss National Supercomputing Centre
2012-2020
École Polytechnique Fédérale de Lausanne
2018-2020
Swisscom (Switzerland)
2012-2020
University of Zurich
2015
Hamburger Fern-Hochschule
2015
Universität Hamburg
2015
University of Portsmouth
2011
Osservatorio Astrofisico di Catania
2011
We analyze the properties of Large Scale Shocks in a cosmological volume size 103Mpc/h simulated with public 1.0.1 release ENZO code. Different methods to identify and characterize shocks post processing are discussed together their uncertainties. Re-ionization affects simulations, we propose fitting procedure model accurately effect re-ionization non--radiative post--processing procedure. investigate by means which uses jumps velocity variables across cells simulations this allows us have...
We have implemented an Adaptive Mesh Refinement criterion explicitly designed to increase spatial resolution around discontinuities in the velocity field ENZO cosmological simulations. With this technique, shocks and turbulent eddies developed during hierarchical assembly of galaxy clusters are followed with unprecedented resolution, even at large distances from center. By measuring spectral properties gas field, its time evolution for a reference cluster, we investigate connection between...
We study the properties of chaotic motions in intra cluster medium using a set 20 galaxy clusters simulated with large dynamical range, Adaptive Mesh Refinement code ENZO (e.g. Norman et al.2007). The adopted setup allows us to spectral and spatial turbulent unprecedented detail, achieving an maximum available Reynolds number order R=500-1000 for largest eddies. correlations between energy these Intra Cluster Medium state host systems are studied, statistical their evolution time support...
The amplification of primordial magnetic fields via a small-scale turbulent dynamo during structure formation might be able to explain the observed in galaxy clusters. magnetisation more tenuous large-scale structures such as cosmic filaments is uncertain, it challenging for numerical simulations achieve required dynamical range. In this work, we present magneto-hydrodynamical cosmological on large uniform grids study seed intracluster medium (ICM) and warm-hot-intergalactic (WHIM). ICM,...
Turbulence is a key ingredient for the evolution of intracluster medium, whose properties can be predicted with high resolution numerical simulations. We present initial results on generation solenoidal and compressive turbulence in medium during formation small-size cluster using highly resolved, non-radiative cosmological simulations, refined monitoring time. In this first series papers, we closely look at one simulated was distinguished by merger around $z \sim 0.3$. separate laminar gas...
Cosmological hydrodynamical simulations are a valuable tool for understanding the growth of large-scale structure and observables connected with this. Yet, comparably little attention has been given to validation studies properties shocks resulting thermal gas between different numerical methods – something immediate importance as gravitational responsible generating most entropy in Universe. Here, we present results statistics shock wave large volume simulated three cosmological codes:...
We study the acceleration of cosmic rays by collisionless structure formation shocks with ENZO grid simulations. Data from FERMI satellite enable use galaxy clusters as a testbed for particle models. Based on advanced cosmological simulations that include different prescriptions gas and physics, we predicted {\gamma}-ray emission to constrain shock efficiency. infer efficiency must be average <0.1% shocks, particularly 2<M<5 merger are mostly responsible thermalisation intracluster medium....
Abstract Recent radio observations with the Low Frequency Array (LOFAR) discovered diffuse emission extending beyond scale of classical halos. The presence such megahalos indicates that amplification magnetic field and acceleration relativistic particles are working in cluster outskirts, presumably due to combination shocks turbulence dissipate energy these regions. Cosmological magnetohydrodynamical (MHD) simulations galaxy clusters suggest solenoidal has a significant budget outskirts...
The origin of extragalactic magnetic fields is still poorly understood. Based on a dedicated suite cosmological magneto-hydrodynamical simulations with the ENZO code we have performed survey different models that may caused present-day in galaxies and galaxy clusters. outcomes these differ cluster outskirts, filaments, sheets voids use to find observational signatures magnetogenesis. With simulations, predict signal radio observations synchrotron emission from cosmic web, Faraday Rotation,...
We present a numerical scheme, implemented in the cosmological adaptive mesh refinement code enzo, to model injection of cosmic ray (CR) particles at shocks, their advection and dynamical feedback on thermal baryonic gas. give description algorithms show tests against analytical idealized one‐dimensional problems. Our implementation is able track CR energy, spatial energy its gas run‐time. This method applied study acceleration evolution volumes, with both fixed variable resolution. compare...
Due to their late formation in cosmic history, clusters of galaxies are not fully hydrostatic equilibrium and the gravitational pull mass at a given radius is expected be entirely balanced by thermal gas pressure. Turbulence may supply additional pressure, recent (X-ray SZ) reconstructions claim pressure support $\sim 5-15\%$ total $R_{\rm 200}$. In this work we show that, after carefully disentangling bulk from small-scale turbulent motions high-resolution simulations galaxy clusters, can...
Galaxy clusters are the most massive gravitationally bound structures in Universe. They grow by accreting smaller a merging process that produces shocks and turbulence intracluster gas. We observed ridge of radio emission connecting galaxy Abell 0399 0401 with Low-Frequency Array (LOFAR) telescope network at 140 megahertz. This requires population relativistic electrons magnetic field located filament between two clusters. performed simulations to show volume-filling distribution weak may...
The cosmic web contains a large fraction of the total gas mass in universe but is difficult to detect at most wavelengths. Synchrotron emission from shock-accelerated electrons may offer chance imaging radio In this work we use 3D cosmological ENZO-MHD simulations (combined with post-processing renormalisation magnetic field bracket for missing physical ingredients and resolution effects) produce models web. study capabilities 13 surveys emission. We find that by LOFAR, SKA1-LOW MWA have...
ABSTRACT Measuring the magnetic field in cosmic filaments reveals how Universe is magnetized and process that it. Using Rotation Measures (RM) at 144 MHz from LoTSS DR2 data, we analyse rms of RM extragalactic component as a function redshift to investigate evolution with filaments. From previous results, find term dominated by contribution (more than 90 per cent). Including an error account for minor local sources, fit data model physical filament field, evolving $B_f = B_{f,0}\,...
Several processes in the Universe convert a fraction of gas kinetic energy into acceleration relativistic electrons, making them observable at radio wavelengths, or contributing to dormant reservoir low-energy cosmic rays structures. We present new suite cosmological simulations, with simple galaxy formation models calibrated work specific spatial resolution, tailored study all most important injection electrons evolving large-sale structures: accretion and merger shocks, feedback from...
Aims. We aim to understand the nature of diffuse radio emission surrounding massive galaxy cluster PSZ2 G083.29-31.03, at z=0.412, already known host a halo. Our investigation was triggered by Radio U-Net, novel machine learning algorithm for detecting emission, which previously applied LOFAR Two Meter Sky Survey (LoTSS). Methods. re-processed LoTSS (120-168 MHz) data and analyzed archival XMM-Newton (0.7-1.2 keV) observations. also optical near-infrared from DESI Legacy Imaging Surveys...
A number of processes in the Universe are known to convert a fraction gas kinetic energy into acceleration relativistic electrons, making them observable at radio wavelengths or contributing dormant reservoir low-energy cosmic rays structures. We present new suite cosmological simulations with simple galaxy formation models calibrated work specific spatial resolution. This have been tailored support studies all most important injection electrons evolving large-sale structures: accretion and...
The recent detection of radio emission extending beyond the scales typically associated with halos challenges our understanding how energy is transferred to non-thermal components on outskirts galaxy clusters, suggesting crucial role mass accretion processes. So far, discoveries have relied visual identification prominent clusters within limited samples. Today, machine learning promises automatically identify an increasing number such sources in wide-area surveys. We aim understand nature...
We report the detection of diffuse radio emission which might be connected to a large-scale filament cosmic web covering 8deg x area in sky, likely associated with z~0.1 over-density traced by nine massive galaxy clusters. In this work, we present observations region taken Sardinia Radio Telescope. Two clusters field host powerful halo sustained violent ongoing mergers and provide direct proof intra-cluster magnetic fields. order investigate presence synchrotron beyond complex system,...
Despite containing about a half of the total matter in Universe, at most wavelengths filamentary structure cosmic web is difficult to observe. In this work, we use large unigrid cosmological simulations investigate how geometrical, thermodynamical and magnetic properties filaments vary with mass redshift (z ≤ 1). We find that average temperature, length, volume field scales well their mass. This reflects role self-gravity shaping enables statistical predictions observational based on also...
Detecting the thermal and non-thermal emission from shocked cosmic gas surrounding large-scale structures represents a challenge for observations, as well unique window into physics of warm-hot intergalactic medium. In this work, we present synthetic radio X-ray surveys large cosmological simulations in order to assess chances jointly detecting web both frequency ranges. We then propose best observing strategies tailored existing (LOFAR, MWA XMM) or future instruments (SKA-LOW SKA-MID,...
The joint analysis of the Dispersion and Faraday Rotation Measure from distant, polarised Fast Radio Bursts may be used to put constraints on origin distribution extragalactic magnetic fields cosmological scales. While combination can in principle give average along line-of-sight, practice this method must with care because it strongly depends assumed magnetisation model large Our simulations show that observation Measures $\geq 1-10 ~\rm rad/m^2$ $\sim 10^2$ will able discriminate between...