Related papers: Galaxy cluster outskirts from the thermal SZ and n…
Cosmological shocks are a critical part of large-scale structure formation, and are responsible for heating the intracluster medium in galaxy clusters. In addition, they are also capable of accelerating non-thermal electrons and protons. In…
Non-thermal radio emission from cosmic ray electrons in the vicinity of merging galaxy clusters is an important tracer of cluster merger activity, and is the result of complex physical processes that involve magnetic fields, particle…
The acceleration of electrons at shock fronts is thought to be responsible for radio relics, extended radio features in the vicinity of merging galaxy clusters. By combining high resolution Adaptive Mesh Refinement Hydro/N-body cosmological…
(Abridged) Radio relics in galaxy clusters are believed to be associated with powerful shock fronts that originate during cluster mergers, and are a testbed for the acceleration of relativistic particles in the intracluster medium.…
X-ray shocks and radio relics detected in the cluster outskirts are commonly interpreted as shocks induced by mergers of sub-clumps. We study the properties of merger shocks in merging galaxy clusters, using a set of cosmological…
We present ALMA measurements of a merger shock using the thermal Sunyaev-Zel'dovich (SZ) effect signal, at the location of a radio relic in the famous El Gordo galaxy cluster at $z \approx 0.9$. Multi-wavelength analysis in combination with…
Cluster mergers drive shocks into the intracluster medium which heat and compress the thermal gas. X-ray observations of shocks can be used to determine the geometry and kinematics of the merger. Merger shocks should also accelerate…
We have investigated evolution of non-thermal emission from relativistic electrons accelerated at around the shock fronts during merger of clusters of galaxies. We estimate synchrotron radio emission and inverse Compton scattering of cosmic…
When galaxy clusters collide, they generate shock fronts in the hot intracluster medium. Observations of these shocks can provide valuable information on the merger dynamics and physical conditions in the cluster plasma, and even help…
Radio relics have been discovered in many galaxy clusters. They are believed to trace shock fronts induced by cluster mergers. Cosmological simulations allow us to study merger shocks in detail since the intra-cluster medium is heated by…
Radio relics in galaxy clusters are extended synchrotron sources produced by cosmic-ray electrons in the $\mu$G magnetic field. Many relics are found in the cluster periphery and have a cluster-centric, narrow arc-like shape, which suggests…
Clusters of galaxies generally form by the gravitational merger of smaller clusters and groups. Major cluster mergers are the most energetic events in the Universe since the Big Bang. Mergers drive shocks into the intracluster gas, and…
We investigate binary mergers of galaxy clusters, the formation of shocks, and the resulting radio relics using three-dimensional simulations. The initial setup consists of two idealized spherical subclusters with a mass ratio below three,…
Clusters of galaxies generally form by the gravitational merger of smaller clusters and groups. Major cluster mergers are the most energetic events in the Universe since the Big Bang. Mergers drive shocks into the intracluster gas, and…
The main component of the intracluster medium (ICM) in clusters of galaxies is represented by the X-ray emitting thermal plasma. In addition, the presence of relativistic electrons and large-scale magnetic fields in a fraction of galaxy…
Recent observations reveal detailed structures of mergers in galaxy clusters. Moving cold fronts could be identified as remnants of subclusters. They are believed to mark the late stage of a merging process. Dynamics, geometry and extension…
We present correlation results for the radio halo power in galaxy clusters with the integrated thermal Sunyaev-Zel'dovich (SZ) effect signal, including new results obtained at sub-GHz frequencies. The radio data is compiled from several…
The nonthermal radiation observed from a handfull of clusters of Galaxies is the proof that particle acceleration occurs in the intracluster medium. It is often believed that shock surfaces associated with either mergers of clusters of…
Deep radio observations of galaxy clusters have revealed the existence of diffuse radio sources ("halos" and "relics") related to the presence of relativistic electrons and weak magnetic fields in the intracluster volume. I will outline our…
Multi-frequency (X-ray, optical and radio) observations of galaxy clusters indicate that the atmospheres of these cosmic structures consist of a complex structure of thermal (hot and warm) and non-thermal (with different origin and spectra)…