Detecting a Unique EBL Signature with TeV Gamma Rays
نویسندگان
چکیده
We discuss prospects for detecting a spectral break in γ-ray spectra of blazars due to the extragalactic background light (EBL) density falling off between the near and mid-IR. A measurable spectral change in the TeV spectra at 1 TeV could arise from a rapid or slow drop in the EBL density above ≈ 1 um. This effect is mediated by the ratio of the near to mid-IR density of EBL. A detection of such a spectral feature could become a clear signature of EBL absorption. A nondetection would give a strong observational constraint to the shape of the EBL spectrum. We present calculations estimating the sensitivity of TeV telescopes for detecting such a break for blazar observations at different redshifts. Subject headings: TeV; Gamma-ray Astronomy, Extragalactic Background Light
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