Abstract Details

Name: SHREYA MUKHERJEE
Affiliation: INTER-UNIVERSITY CENTRE FOR ASTRONOMY AND ASTROPHYSICS
Conference ID: ASI2025_596
Title : Study of Baryonic Effects on Matter Power Spectrum, and Dark Energy Equation of State Parameter using Cosmic Shear
Authors and Co-Authors : Shreya Mukherjee 1, Surhud More 1,2
Abstract Type : Oral
Abstract Category : Galaxies and Cosmology
Abstract : We present cosmological constraints on dark energy equation of state parameter ‘w’ from the cosmic shear two-point correlation function measured by a the weak lensing analysis of the Subaru HSC survey. When combined with likelihood from Supernovae of type Ia and Baryon Acoustic Oscillation data, our analysis constrains w = -1.144+0.102-0.096 with 68% confidence, which is consistent with the cosmological constant. We also infer the value of the parameter S8, which characterizes the amplitude of clustering or matter density fluctuations, to be 0.751±0.027 with 68% confidence. We also utilize model agnostic prescription of the baryonic feedback processes such as star formation, AGN feedback and their effects on the matter-power spectrum and infer the power spectrum suppression required to explain the cosmic shear data on small scales. This suppression can be tested using the galaxy-galaxy lensing signal from data, to address the degeneracy between cosmological parameters and baryonic feedback effects.