The extragalactic background light: lower vs upper limits

Abstract

The discovery of distant sources of very high energy (VHE) gamma-rays with hard energy spectra enabled to derive strong upper limits on the density of the extragalactic background light (EBL). These limits are close to the lower limits derived from deep source counts. A recent re-determination of the EBL contribution from resolved sources at 3.6 micrometer finds a higher EBL density, which is claimed to be in conflict with the assumptions utilized to derive the EBL upper limits from VHE spectra. Here, it is shown that is possible to recover the canonical Gamma~1.5 intrinsic spectra for such a higher EBL density.

4 pages, 2 figures, 1 table. Contribution to the proceedings of the 2nd Heidelberg Workshop: "High-Energy Gamma-rays and Neutrinos from Extra-Galactic Sources"

References in corpus (5)

• New constraints on the Mid-IR EBL from the HESS discovery of VHE gamma rays from 1ES 0229+200
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• Probing the 3.6 Micron CIRB with Spitzer in 3 DIRBE Dark Spots
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