Measurement of the extragalactic background light spectral energy distribution with VERITAS
astro-ph.HE
/ Authors
VERITAS collaboration, A. U. Abeysekara, A. Archer, W. Benbow, R. Bird, A. Brill, R. Brose, M. Buchovecky, J. L. Christiansen, W. Cui
and 52 more authors
M. K. Daniel, A. Falcone, Q. Feng, M. Fernandez-Alonso, J. P. Finley, L. Fortson, A. Furniss, A. Gent, C. Giuri, O. Gueta, D. Hanna, T. Hassan, O. Hervet, J. Holder, G. Hughes, T. B. Humensky, C. A. Johnson, P. Kaaret, M. Kertzman, D. Kieda, M. Krause, F. Krennrich, S. Kumar, M. J. Lang
/ Abstract
The extragalactic background light (EBL), a diffuse photon field in the optical and infrared range, is a record of radiative processes over the Universe's history. Spectral measurements of blazars at very high energies ($>$100 GeV) enable the reconstruction of the spectral energy distribution (SED) of the EBL, as the blazar spectra are modified by redshift- and energy-dependent interactions of the gamma-ray photons with the EBL. The spectra of 14 VERITAS-detected blazars are included in a new measurement of the EBL SED that is independent of EBL SED models. The resulting SED covers an EBL wavelength range of 0.56--56 $μ$m, and is in good agreement with lower limits obtained by assuming that the EBL is entirely due to radiation from cataloged galaxies.