ON WEAK REDSHIFT DEPENDENCE OF GAMMA-RAY SPECTRA OF DISTANT BLAZARS

Essey, Warren; Kusenko, Alexander

doi:10.1088/2041-8205/751/1/L11

Title: ON WEAK REDSHIFT DEPENDENCE OF GAMMA-RAY SPECTRA OF DISTANT BLAZARS

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Abstract

Line-of-sight interactions of cosmic rays provide a natural explanation of the hard gamma-ray spectra of distant blazars, which are believed to be capable of producing both gamma rays and cosmic rays. For sources with redshifts z {approx}> 0.1, secondary gamma rays produced in cosmic-ray interactions with background photons close to an observer can dominate over primary gamma rays originating at the source. The transition from one component to another is accompanied by a change in the spectral index depending on the source redshift. We present theoretical predictions and show that they agree with the data from Fermi Large Area Telescope. This agreement, combined with the spectral data from Atmospheric Cherenkov Telescopes, provides evidence of cosmic-ray acceleration by active galactic nuclei and opens new opportunities for studying photon backgrounds and intergalactic magnetic fields.

Authors:

Essey, Warren ^[1]; Kusenko, Alexander ^[2]

International Center for Computer Science, University of California, Berkeley, CA 94720 (United States)
Department of Physics and Astronomy, University of California, Los Angeles, CA 90095-1547 (United States)

Publication Date:: Sun May 20 00:00:00 EDT 2012

OSTI Identifier:: 22047817

Resource Type:: Journal Article

Journal Name:: Astrophysical Journal Letters

Additional Journal Information:: Journal Volume: 751; Journal Issue: 1; Other Information: Country of input: International Atomic Energy Agency (IAEA); Journal ID: ISSN 2041-8205

Country of Publication:: United States

Language:: English

Subject:: 79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ACCELERATION; ASTROPHYSICS; BL LACERTAE OBJECTS; CHERENKOV COUNTERS; COSMIC PHOTONS; COSMIC RADIATION; GALAXIES; GALAXY NUCLEI; GAMMA RADIATION; GAMMA SPECTRA; INDEXES; INTERGALACTIC SPACE; MAGNETIC FIELDS; QUASARS; RED SHIFT; TELESCOPE COUNTERS; TELESCOPES

Citation Formats


                    Essey, Warren, and Kusenko, Alexander. ON WEAK REDSHIFT DEPENDENCE OF GAMMA-RAY SPECTRA OF DISTANT BLAZARS.  United States: N. p., 2012. 
        Web.  doi:10.1088/2041-8205/751/1/L11.

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                    Essey, Warren, & Kusenko, Alexander. ON WEAK REDSHIFT DEPENDENCE OF GAMMA-RAY SPECTRA OF DISTANT BLAZARS.  United States.  https://doi.org/10.1088/2041-8205/751/1/L11

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                    Essey, Warren, and Kusenko, Alexander. 2012.  
        "ON WEAK REDSHIFT DEPENDENCE OF GAMMA-RAY SPECTRA OF DISTANT BLAZARS".  United States.  https://doi.org/10.1088/2041-8205/751/1/L11.

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@article{osti_22047817,

  title        = {ON WEAK REDSHIFT DEPENDENCE OF GAMMA-RAY SPECTRA OF DISTANT BLAZARS},

  author       = {Essey, Warren and Kusenko, Alexander},

  abstractNote = {Line-of-sight interactions of cosmic rays provide a natural explanation of the hard gamma-ray spectra of distant blazars, which are believed to be capable of producing both gamma rays and cosmic rays. For sources with redshifts z {approx}> 0.1, secondary gamma rays produced in cosmic-ray interactions with background photons close to an observer can dominate over primary gamma rays originating at the source. The transition from one component to another is accompanied by a change in the spectral index depending on the source redshift. We present theoretical predictions and show that they agree with the data from Fermi Large Area Telescope. This agreement, combined with the spectral data from Atmospheric Cherenkov Telescopes, provides evidence of cosmic-ray acceleration by active galactic nuclei and opens new opportunities for studying photon backgrounds and intergalactic magnetic fields.},

  doi          = {10.1088/2041-8205/751/1/L11},

  url          = {https://www.osti.gov/biblio/22047817},
  journal      = {Astrophysical Journal Letters},

  issn         = {2041-8205},

  number       = 1,

  volume       = 751,

  place        = {United States},

  year         = {Sun May 20 00:00:00 EDT 2012},

  month        = {Sun May 20 00:00:00 EDT 2012}

}

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https://doi.org/10.1088/2041-8205/751/1/L11

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