Abstract Details
| Name: Reju Sam John Affiliation: Pondicherry University Conference ID: ASI2015_535 Title : Evolution of the energy distribution in the Intracluster Medium during large scale structure formation Authors and Co-Authors : Surajit Paul, Dept. of Physics, University of Pune. Harish Kumar, Dept. of Physics, Pondicherry Engineering College. Abstract Type : Poster Abstract Category : General Relativity and Cosmology Abstract : In the hierarchical structure formation framework, galaxy clusters are the biggest objects in the universe. They grow by continuous accretion and mergers, which in turn induce turbulence flow and shock wave. This large-scale shocks can be an important sources of cosmic rays (CRs) in the universe. These cosmic rays are extremely important as it can efficiently influence the structure formation and evolution. Since the galaxy cluster merger has a large evolution time (>Giga years), it is impossible to observe the entire evolution, but only a snap shot of the different stages. Simulation of such events thus became inevitable. We performed cosmological hydrodynamic simulations using ENZO 2.2 to study the galaxy cluster merger and hence the large-scale shocks. Shock finding in our simulations is accomplished by means of unsplit velocity jumps across the simulation grids. In particular, we studied the evolution of both thermal and non thermal energy released during merger event. This enabled us to compute the thermal energy fraction transferred to cosmic-rays by diffusive shock acceleration (DSA). Using the scaling law computed by Kang et al. 2007, we computed the cosmic ray fraction in the merging galaxy systems. We found a nice correlation among the mass of the merging galaxy-clusters and cosmic ray flux emanating out of the system. We also found during the mergers, cosmic ray flux goes up by many times. Correlation of merging phases and cosmic ray flux will definitely help us to decide the state of different observed galaxy clusters. |