Abstract Details

Name: Sandhya Jagannathan
Affiliation: University of Delhi
Conference ID: ASI2020_513
Title : Impact of magnetic field on the gas mass fraction of galaxy clusters
Authors and Co-Authors : Sandhya Jagannathan, Sunil Malik, Deepak Jain, and T.R. Seshadri
Abstract Type : Poster
Abstract Category : Extragalactic Astronomy
Abstract : Magnetic field has been observed in both relaxed as well as unrelaxed galaxy clusters with the former possessing more strength compared to the latter. The non-thermal pressure exerted by magnetic fields contributes to the total pressure in galaxy clusters and in turn affects the estimates of the gas mass fraction, fgas. In our study, we have considered a magnetic field strength of 10micro Gauss for 22 unrelaxed clusters and a field strength of 10micro Gauss as well as 20micro Gauss for 13 relaxed clusters. The role of magnetic field has been taken into account in inferring the gas density distribution through the modification of the hydrostatic equilibrium condition (HSE). We have found that the resultant gas mass fraction is smaller with magnetic field as compared to that without magnetic field. However, this decrease is dependent on the strength and the profile of the magnetic field. We have also determined the total mass using the NFW profile to check for the dependency of fgas estimates on total mass estimators. Further, we have noted that the fgas estimates from NFW are closer to that derived from WMAP results as compared to those from HSE. From our analysis, we conclude that the non-thermal pressure from magnetic fields has a non-zero but minor impact (of upto 4 %) on the gas mass fraction of galaxy clusters.