Lyman-A Escape Fraction Corrections Approaches in Astro Stimulations

Haifeng Guo

doi:10.54097/5zfmcn96

Authors

Haifeng Guo

DOI:

https://doi.org/10.54097/5zfmcn96

Keywords:

Lyman-alpha emission, escape fraction, Star forming observations, Lyman-alpha absorption.

Abstract

The escape of photons from galaxies plays a critical role in understanding high-redshift star-forming galaxies (SFGs) and their contribution to cosmic reionization. This study examines the factors influencing the escape fraction ( ), with a focus on the effects of dust, gas dynamics, and intergalactic medium (IGM) interactions. This work presents two methods for estimating escape, comparing them with existing observational data. The findings highlight the challenges in detecting emission in dusty galaxies and propose new techniques to account for the influence of dust attenuation and turbulent velocities on photon escape.By utilizing data from the THESAN cosmological simulations and considering local gas properties, this work develops a simple model of emission using extinction.By another independent stimulation statistic code, this work develop a more refined model incorporating corrections for local temperature, turbulent velocities, and dust absorption. The results suggest a better understanding of the relationship between dust, gas dynamics, and photon escape, with implications for studies of galaxy formation, star formation rates, and the impact of reionization. It provides direct correction with quantities including dust optical depth, temperature, hydrogen density and turbulent velocity. Further research will focus on refining this model with additional observations and complex gas kinematics.

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