Measurement of the EBL spectral energy distribution using the VHE
  gamma-ray spectra of H.E.S.S. blazars
  Very high-energy gamma-rays (VHE, E>100 GeV) propagating over cosmological
distances can interact with the low-energy photons of the extragalactic
background light (EBL) and produce electron-positron pairs. The transparency of
the universe to VHE gamma-rays is then directly related to the spectral energy
distribution (SED) of the EBL. The observation of features in the VHE energy
spectra of extragalactic sources allows the EBL to be measured, which otherwise
is very difficult to determine. An EBL-model independent measurement of the EBL
SED with the H.E.S.S. array of Cherenkov telescopes is presented. It is
obtained by extracting the EBL absorption signal from the reanalysis of
high-quality spectra of blazars. From H.E.S.S. data alone the EBL signature is
detected at a significance of 9.5 sigma, and the intensity of the EBL obtained
in different spectral bands is presented together with the associated gamma-ray
horizon.
