The Effect of AGN and SNe Feedback on Star Formation, Reionization and the Near Infrared Background

Abstract

Feedback from supernovae (SNe) and from active galactic nuclei (AGN) accompanies the history of star formation and galaxy evolution. We present an analytic model to explain how and when the SNe and AGN exert their feedback effects oil the star formation and galaxy evolution processes. By using SNe and AGN kinetic feedback mechanisms based on the Lambda Cold Dark Matter (LCDM) model, we explore how these feedback mechanisms affect the star formation history (SFH), the Near-Infrared Background (NIRB) flux and the cosmological reionization. We find the values of the feedback strengths, epsilon(AGN) = 1.0(-0.3)(+0.5) and epsilon(SN) = 0.04(-0.02)(+0.02), can provide a reasonable explanation of most of the observational re sults, and that the AGN feedback effect on star formation history is quite different from the SNe feedback at high redshifts. Our conclusions manifest quantitatively that these feedback effects decrease star formation rate density (SFRD) and the NIRB flux (in 1.4 - 4.0 mu m), and postpone the time of completion of the cosmological reionization.