Abstract Details

Name: Barun Maity
Affiliation: National Centre for Radio Astrophysics
Conference ID: ASI2021_63
Title : Inclusion of inhomogeneous recombination and feedback in SCRIPT
Authors and Co-Authors : Barun Maity, Tirthankar Roy Choudhury, NCRA-TIFR
Abstract Type : Poster
Abstract Category : General Relativity and Cosmology
Abstract : One of the least understood phases in the Universe is the epoch of reionization (EoR) when the hydrogen (mainly) in the Universe got ionized by ultra-violet radiation from first stars. In spite of having a wealth of observational data at different wavelengths from different telescopes, there is no clear understanding of the physical processes that were relevant in this epoch. The precise extent of this phase is still unknown. This regime can be tracked via redshifted 21 cm signal coming from neutral hydrogen atoms. In general there are two possible ways to model the 21 cm signal i.e using the full radiative simulations and using semi-analytical/semi-numerical techniques. The second method includes some physically motivated assumptions/approximations but computationally less expensive than the full radiative simulations and hence is useful for probing the unknown parameter space. The most popular technique for computing the 21 cm signal using the semi-analytical method is based on excursion sets. These models, however, do not conserve the number of ionizing photons which result in non-converging power spectrum with respect to the resolution of the simulation. More recently, these difficulties have been solved in an explicitly photon-conserving semi-numerical model which is named as SCRIPT (Semi Numerical Code for ReionIzation with PhoTon Conservation (Choudhury & Paranjape, 2018). The present implementation of SCRIPT does not include physical processes like the inhomgeneous recombination and radiative feedback. These effects can play important roles in deciding the reionization history. In this work, we incorporate these two effects in SCRIPT and study the consequences. This allows us to obtain constraints on reionization in the presence of the two effects.