Periodic Reporting for period 4 - MAGCOW (The Magnetised Cosmic Web)
Periodo di rendicontazione: 2022-03-01 al 2023-03-31
All publications produced in the course of the project are closely related to the above topic, in the attempt of obtaining the widest and most complete ever of the origin
and effects of cosmic magnetism at cosmological scales.
To this end, in our projects we investigated, both, purely theoretical models of the cosmic web, real observations, or combined the two methods.
All publications of the project were made timely available via the arXiv repository (www.arxiv.org) always soon after official acceptance by the editors, and often even before this, as preprints.
Moreover, the open access to all publications produced by the project is also timely enabled by its submission to the https://cris.unibo.it(si apre in una nuova finestra) open access official repository of the University of Bologna.
We produced more than a hundred peer-review publications during the granting period (the exact number is not settled as several papers are in the course of acceptance and proof-reading with different journals as in the moment of writing).
Several of our works ended up being published in the highest ranking scientific journals: Science (1), Nature (1), Nature Astronomy (2), Science Advances (2) and Physical Review Letters (2).
Modelling of existing radio data, guided by theoretical analysis.
Continuous activity of proposing new radio observation (to be gained through international and competitive call for applications of observing time) to fill existing gaps in our understanding of cosmic magnetism and evolution.
Innovative analysis and modelling techniques to extract information on cosmic magnetism from radio observations, and connect them with the physical expectations and scenarios of our numerical simulations.
Simulations of small-scale interactions between cosmic rays and magnetic fields, using Particle-In-Cell simulations, and extrapolation of these data on larger scales.
Connection between cosmic magnetism and cosmology, through the usage of complex network analysis techniques.
This allowed us to connect observations and theory with unprecedented realism and depth of inference.
In detail, from the theoretical and numerical viewpoint, we
- produced the first successful simulation ever of the growth of small-scale dynamo in a simulated galaxy clusters with the ENZO-MHD code;
- produced the complete suite of cosmological MHD simulations to-date (more than 30 models) comparing the observable outcomes of magnetogenesis scenarios on different scales;
- produced the first simulations of primordial magnetogenesis scenarios, also connected with Local Universe resimulations and updated constraints from the CMB analysis;
- produced the first predictions for the synchrotron polarisation signatures from the shocked cosmic web, as well as for very long lightcones of Faraday Rotation measurements for different scenarios, up to redshift 3.
- produced the first sophisticated numerical investigations of new mechanism to (pre)accelerate radio emitting electrons in merging clusters of galaxies, to study new regimes of particle acceleration discovered within the activity or collaborations of MAGCOW.
From the observational view point, we
- participated to the first discovery of "Radio Bridges" between pre-merger clusters of galaxies;
- participated to the first discovery of "Mega Radio Halos", a new class of radio sources extending much beyond classical radio halos;
- participated to the fist detection of the shocked cosmic web via stacking, both in total intensity & polarisation;
- participated to the detection of the statistical signature of cosmic magnetism from filaments in faraday rotation observations;
- discovered a new, faint class of radio relics, likely to be entirely powered by weak shock direct acceleration:
- explored new, uncharted territory in the production of faint and filamentary radio emission within the substructures of giant radio relics.