CaltechAUTHORS
Published October 2011 | Version public
Journal Article Metadata-only

Determination of intergalactic magnetic fields from gamma ray data

Creators

  • 1. ROR icon University of California, Los Angeles
  • 2. ROR icon California Institute of Technology
  • 3. ROR icon Kavli Institute for the Physics and Mathematics of the Universe

Abstract

We report a measurement of intergalactic magnetic fields using combined data from Atmospheric Cherenkov Telescopes and Fermi Gamma-Ray Space Telescope, based on the spectral data alone. If blazars are assumed to produce both gamma rays and cosmic rays, the observed spectra are not sensitive to the intrinsic spectrum of the source, because, for a distant blazar, secondary photons produced along the line of sight dominate the signal. In this case, we set a limit 1 x 10^(-17) G < B < 3 x 10^(-14) G. If one excludes the cosmic-ray component, the 10^(-17) G lower limit remains, but the upper limit depends on the spectral properties of the source. We present the allowed ranges for a variety of model parameters.

Additional Information

© 2011 Elsevier B.V. Received 1 April 2011; revised 15 June 2011; Accepted 21 June 2011. Available online 1 July 2011. The authors thank F. Aharonian, J. Beacom, P. Blasi, C. Dermer, S. Razzaque, and E. Waxman for helpful comments. The work of W.E. and A.K. was supported by DOE grant DE-FG03-91ER40662 and NASA ATP grant NNX08AL48G. The work of S.A. was supported by Japan Society for Promotion of Science.

Additional details

Identifiers

Eprint ID
28318
Resolver ID
CaltechAUTHORS:20111206-114000364

Funding

Department of Energy (DOE)
DE-FG03-91ER40662
NASA ATP
NNX08AL48G
Japan Society for the Promotion of Science

Dates

Created
2011-12-06
Created from EPrint's datestamp field
Updated
2021-11-09
Created from EPrint's last_modified field