EBL constraints with VERITAS gamma-ray observations

M. FERNANDEZ ALONSO, VERITAS COLLABORATION: A.C. ROVERO

San Juan

Congreso; 59 Reunión Anual de la Asociación Argentina de Astronomía; 2016

ICATE

The extragalactic background light (EBL) contains all the radiation emitted by nuclear and accretion processes since the epoch of recombination. Direct measurements of the EBL in the near-IR to mid-IR waveband are extremely difficult due mainly to the zodiacal light foreground. Instead, gamma-ray astronomy offers the possibility to indirectly set limits to the EBL by studying the effects of gamma-ray absorption in the spectra of detected sources in the very high energy range (VHE: >100 GeV). These effects can be generally seen in thespectra of VHE blazars as a softening (steepening) of the spectrum and/or abrupt changes in the spectral index or breaks. In this work we use recent VERITAS data of a group of blazars and apply two methods to derive constraints for the EBL spectral properties. We present preliminary results that will be completed with new observations in the near future to enhance the calculated restrictions to the EBL.