An empirical approach to the extragalactic background light from AEGIS galaxy SED-type fractions

Abstract

Abstract. The extragalactic background light (EBL) is of fundamental importance both for understanding the entire process of galaxy evolution and for γ-ray astronomy. However, the overall spectrum of the EBL between 0.1 and 1000 µm has never been determined directly, neither from observed luminosity functions (LFs), over a wide redshift range, nor from any multiwavelength observation of galaxy spectral energy distributions (SEDs). The evolving overall spectrum of the EBL is derived here utilizing a novel method based on observations only. It is emphasized that the local EBL seems already well constrained from the UV up to the mid-IR. Different independent methodologies such as direct measurement, galaxy counts, γ-ray attenuation and realistic EBL modelings point towards the same EBL intensity level. Therefore, a relevant contribution from Pop III stars to the local EBL seems unlikely.

The Extragalactic Background Light: The Emission from All Stars and Black Holes

“…There have been a great variety of methodologies intended to exploit the gamma-ray attenuation approach. A comprehensive review on this can be found in [6], while a concise summary about EBL observational strategies is available in [7]. In the following I will present some of the current techniques, based mostly on gamma-ray observations, and discuss also the major problems affecting them.…”