| Name: | Prateek Gupta |
| Affiliation: | Thüringer Landessternwarte Tautenburg |
| Conference ID : | ASI2024_825 |
| Title : | Modelling Non-thermal Radio Emission from Galaxy Clusters and where they meet Filaments and Voids |
| Authors : | Prateek Gupta,1,2, Surajit Paul,1,3 |
| Authors Affiliation: | 1 Prateek Gupta, Surajit Paul Affiliation (Department of Physics, Savitribai Phule Pune University, Pune - 411007, India)
2 Prateek Gupta Affiliation (Thüringer Landessternwarte, Sternwarte 5, Tautenburg-07778, Germany)
3 Surajit Paul Affiliation (Manipal Centre for Natural Sciences, Centre of Excellence, Manipal Academy of Higher Education, Manipal, Karnataka-576104, India) |
| Mode of Presentation: | Oral |
| Abstract Category : | Thesis |
| Abstract : | The formation and evolution of galaxy clusters ignite the most energetic particle accelerators in the Universe in the form of mega-parsec scale shocks and turbulence in the system. These energetic processes thermalize the medium, as well as modify the non-thermal energy budget in galaxy clusters, i.e., turbulent energy density, magnetic field amplification, and production of CR particles. The signature of diffuse synchrotron radio emission from the intra-cluster medium (ICM) is the most direct evidence of such non-thermal processes. So far, many charged particle acceleration mechanisms, i.e., diffusive shock acceleration (DSA) and turbulence re-acceleration (TRA), have been proposed to explain the cluster scale radio structures. However, how far these models are applicable to clusters in a wide mass range, is not yet addressed. Furthermore, the non-promising observing fractions as predicted by analytical solutions for the poor clusters, has demotivated the systematic observations in a wide mass range, creating a vacuum of information, especially in lower mass end. The same has been the focus of this thesis research work, a maiden attempt to bridge this gap. Through utilising N-body+hydro-dynamical cosmological simulations, we captured the cluster shock and turbulence efficiently, and semi-analytically modelled the synchrotron radio emission in a mock sample of 600 simulated galaxy clusters having wide mass range (10^{13}-10^{15}Msun). Our work shows that DSA-and-TRA models can successfully reproduce the radio emission morphology and its detectability for high mass range (>10^{14}Msun). Moreover, it reveals that a fraction of low mass systems are even within the detection limit of existing most sensitive radio telescopes, which may give a strong motivation for systematic studies for the future radio cosmologist. By implementing TRA with variable spectra, we address the major issue of all time, why some galaxy clusters have radio emission from the central region and some do not? |
