The Fraction of Ionizing Photons Escaping from High-Redshift Galaxies
Jhan A Srbinovsky, J Stuart B Wyithe
PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF AUSTRALIA | CAMBRIDGE UNIV PRESS | Published : 2010
The fraction (fesc) of ionizing photons that escape their host galaxy and so are able to ionize hydrogen in the intergalactic medium is a critical parameter in studies of the reionization era. In this paper we constrain fesc at high redshift by modelling the observed Ly transmission. Using an N-body simulation of the cosmic web, we first model an ionizing background due to star-bursting galaxies. We then extract an ensemble of mock absorption spectra from the simulation and compute the mean transmission. We adjust the free parameter, fesc in our model of the ionizing background to reproduce the observed transmission. We find that f esc increases with the minimum galaxy mass considered to con..View full abstract
We thank Adam Lidz for providing the N-body simulation and technical assistance, and also the Institute for Theory and Computation at CfA (Harvard-Smithsonian) for use of their computational facilities during this project. This work was supported in part by the Australian Research Council. J.A.S. acknowledges the support of an Australian Postgraduate Award.