Speaker
Kari Helgason
(Max Planck Institute for Astrophysics)
Description
The Extragalactic Background Light (EBL) absorbs gamma-rays (γγ->e-e+) and leaves a characteristic imprint in the spectra of high energy blazars. Utilizing the new Fermi-LAT measurement of the gamma-ray optical depth at 0<z<3, we reconstruct the detailed build-up of the EBL over cosmic time in a model-independent way. We use an MCMC approach to determine the instantaneous luminosity density of galaxy populations from the UV to the near-IR out to z~6. This allows us to constrain both the cosmic star formation rate density and the build-up of stellar mass over 90% of cosmic time. We also present limits on the amount light from faint undetected galaxies during the epoch of reionization.
Primary author
Kari Helgason
(Max Planck Institute for Astrophysics)
Co-authors
Abhishek Desai
(Clemson University)
Alberto Dominguez
(Universidad Complutense de Madrid)
Justin Finke
(US Naval Research Laboratory)
Prof.
Marco Ajello
(Clemson University)
Vaidehi Sharan Paliya`
(Clemson University)
