Exploring First Stars Era with GLAST

TL;DR

This paper discusses how observations of gamma-ray sources with GLAST can reveal the properties of the universe's first stars by detecting specific absorption features caused by the cosmic infrared background.

Contribution

It proposes using GLAST observations of high-redshift gamma-ray sources to study the first stars era through absorption features in their spectra.

Findings

CIB fluctuations indicate significant early star formation

Absorption features in high-z GRB spectra can reveal first stars properties

Method to probe early universe with gamma-ray observations

Abstract

Cosmic infrared background (CIB) includes emissions from objects inaccessible to current telescopic studies, such as the putative Population III, the first stars. Recently, strong direct evidence for significant CIB levels produced by the first stars came from CIB fluctuations discovered in deep Spitzer images. Such CIB levels should have left a unique absorption feature in the spectra of high-z GRBs and blazars as suggested in [4]. This is observable with GLAST sources at z>2 and measuring this absorption will give important information on energetics and constituents of the first stars era.