{
  "id": "1503.04860",
  "version": "v1",
  "published": "2015-03-16T21:30:00.000Z",
  "updated": "2015-03-16T21:30:00.000Z",
  "title": "On conservative models of \"the pair-production anomaly\" in blazar spectra at Very High Energies",
  "authors": [
    "T. A. Dzhatdoev"
  ],
  "comment": "8 pages, 4 figures. This paper tries to summarize the status of the field by the end of January, 2015",
  "categories": [
    "astro-ph.HE"
  ],
  "abstract": "For some blazars, the gamma-ray absorption features due to pair-production on the Extragalactic Background Light (EBL) are fainter than expected. The present work reviews the main models that could explain this paradox, with emphasis on conservative ones, that do not include any new physics. The models that are intrinsic to the source, do allow a very hard primary spectrum, but fail to explain a regular redshift dependence of the anomaly starting energy. The model that includes a contribution from secondary photons produced by cosmic rays (CR) near the Earth seems to require a well collimated CR beam, what is hard to achieve. Finally, the model with secondary photons produced in electromagnetic (EM) cascades initiated by primary gamma-rays is considered. In principle, it allows to decrease the statistical significance of the anomaly and, while requiring quite low EGMF strength B, does not contradict to most contemporary constraints on the B value. Additionally, it is shown that the recently observed correlation between directions to hard gamma-ray sources and voids in the Large Scale Structure is a natural feature of the EM cascade model.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2015-03-16T21:30:00.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "high energies",
      "blazar spectra",
      "conservative models",
      "pair-production anomaly",
      "secondary photons"
    ],
    "publication": {
      "doi": "10.1088/1742-6596/632/1/012035",
      "journal": "Journal of Physics Conference Series",
      "year": 2015,
      "month": "Aug",
      "volume": 632,
      "number": 1,
      "pages": "012035"
    },
    "note": {
      "typesetting": "TeX",
      "pages": 8,
      "language": "en",
      "license": "arXiv",
      "status": "editable",
      "adsabs": "2015JPhCS.632a2035D",
      "inspire": 1353081
    }
  }
}