1996/08/13 by F. W. Stecker, O. C. de Jager · 2 citations
Physics and Astronomy · #Astrophysics and Cosmic Phenomena #Galaxies: Formation, Evolution, Phenomena #Radio Astronomy Observations and Technology #astro-ph
paper · pdf · doi:10.1086/303668
Plain TeX file with text in abs96.tex, 3 postscript figures (Fig. 1 - ircobe.eps, Fig. 2 - taupl.eps, Fig. 3 - mki.eps), stylefile epsf.sty included, accepted for publication in the Astrophysical Journal
arxiv created 1996/08/13 · openalex publication_date 1997/02/20 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/31
We present a new calculation of the intergalactic γ-ray pair-production absorption coefficient as a function of both energy and redshift up to the redshift of 3C 279, z = 0.54. In reexamining this problem, we make use of new observational data on the intergalactic infrared radiation field (IIRF), together with recent theoretical models of the galactic spectral energy distributions of the IIRF from stars and dust reradiation and estimates of the IIRF from galaxy counts and COBE results. We present our results for two fairly well defined IIRF spectral energy distributions, one which is within 1 σ of our previous estimate of the IIRF at ~20 μm. Then we apply our results to the γ-ray spectrum of Mrk 421 and obtain good agreement with the observational data, including the recent results of the HEGRA group.