Pointlike gamma ray sources as signatures of distant accelerators of ultrahigh energy cosmic rays.

  title={Pointlike gamma ray sources as signatures of distant accelerators of ultrahigh energy cosmic rays.},
  author={Stefano Gabici and Felix Aharonian},
  journal={Physical review letters},
  volume={95 25},
We discuss the possibility of observing distant accelerators of ultrahigh energy cosmic rays in synchrotron gamma rays. Protons propagating away from their acceleration sites produce extremely energetic electrons during photopion interactions with cosmic microwave background photons. If the accelerator is embedded in a magnetized region, these electrons will emit high energy synchrotron radiation. The resulting synchrotron source is expected to be pointlike, steady, and detectable in the GeV… 
Gamma ray signatures of ultra high energy cosmic ray accelerators: electromagnetic cascade versus synchrotron radiation of secondary electrons
Abstract We discuss the possibility of observing ultra high energy cosmic ray sources in high energy gamma rays. Protons propagating away from their accelerators produce secondary electrons during
Gamma Rays from Ultra-High-Energy Cosmic Rays in Cygnus A
Ultra-high-energy cosmic rays (UHECRs) accelerated in the jets of active galactic nuclei can accumulate in high magnetic field, ~100 kpc-scale regions surrounding powerful radio galaxies.
Origin of ultra-high energy cosmic rays in the era of Auger and Telescope Array
We discuss the origin of ultra-high energy cosmic rays in light of the latest observational results from the Pierre Auger Observatory, highlighting potential astrophysical sources such as active
Non-variable cosmologically distant gamma-ray emitters as a propagation imprint of ultra-high-energy protons
The acceleration sites of ultra-high-energy (UHE) protons can be traced by the footprint left by these particles when they propagate through cosmic microwave background (CMB) radiation. Secondary
Secondary gamma rays from ultrahigh energy cosmic rays produced in magnetized environments
Nearby sources of cosmic rays up to a ZeV(=10{sup 21} eV) could be observed with a multimessenger approach including secondary {gamma}-rays and neutrinos. If cosmic rays above {approx}10{sup 18} eV
Constraining the Emissivity of Ultrahigh Energy Cosmic Rays in the Distant Universe with the Diffuse Gamma-ray Emission
Ultra-high cosmic rays (UHECRs) with energies & 10 19 eV emitted at cosmological distances will be attenuated by cosmic microwave and infrared background radiation through photohadronic processes.
Detectability of ultrahigh energy cosmic-ray signatures in gamma-rays
The injection of ultrahigh energy cosmic-rays in the intergalactic medium leads to the production of a GeV–TeV gamma-ray halo centered on the source location, through the production of a high
The Astrophysics of Ultrahigh-Energy Cosmic Rays
The origin of the highest energy cosmic rays is still unknown. The discovery of their sources is expected to reveal the workings of the most energetic astrophysical accelerators in the Universe.
Constraints on the origin of ultra-high-energy cosmic rays from cosmogenic neutrinos and photons
We study the production of cosmogenic neutrinos and photons during the extragalactic propagation of ultra-high-energy cosmic rays (UHECRs). For a wide range of models in cosmological evolution of
The photomeson production in ultra-high-energy cosmic-ray (UHECR) accelerators such as ?-ray bursts and active galaxies may lead to ultra-high-energy (UHE) ?-ray emission. We show that the generation


Ultra high energy cosmic rays: the theoretical challenge
Abstract The origin of the highest-energy cosmic rays remains a mystery. The lack of a high-energy cutoff in the cosmic-ray spectrum together with an apparently isotropic distribution of arrival
Ultrahigh energy photons, electrons, and neutrinos, the microwave background, and the universal cosmic-ray hypothesis
The production of ultrahigh energy photons, electrons and neutrinos as the decay products of pions produced in photomeson interactions between cosmic-ray nucleons and the blackbody microwave
Delayed GeV-TeV Photons from Gamma-Ray Bursts Producing High-Energy Cosmic Rays
A scenario in which cosmic rays (CRs) above 1020 eV are produced by cosmological gamma-ray bursts (GRBs) is consistent with observations, provided that deflections by the intergalactic magnetic field
Primary cosmic γrays above 1012 eV
An analysis is made of the interactions of very energetic cosmic ray primaries with the universal black body radiation in extragalactic space. The gamma rays from the initial pi 0 mesons produce
The effective penetration distance of ultrahigh-energy electrons and photons traversing a cosmic blackbody photon gas
The effective average energy loss for an energetic (E> or approx. =10/sup 15/eV) particle traversing the microwave background radiatio is evaluated. Electron-photon transformations by Compton
Spectrum of the Extra-galactic Background Radiation at Low Radio Frequencies
Results of recent analyses of metre-wave measurements place the brightness I x of the isotropic component at about one-third the minimum total brightness observed at a frequency f of 100 MHz.
Proton-synchrotron radiation of large-scale jets in active galactic nuclei
The X-radiation of large-scale extragalactic jets poses a serious challenge for the conventional electron-synchrotron or inverse Compton models suggested to explain the overall non-thermal emission
Photohadronic Processes in Astrophysical Environments
We discuss the first applications of our newly developed Monte Carlo event generator SOPHIA to multiparticle photoproduction of relativistic protons with thermal and power-law radiation fields. The
Clusters of Galaxies as Storage Room for Cosmic Rays
It is demonstrated that clusters of galaxies are able to keep cosmic rays for a time exceeding the age of the universe. This phenomenon reveals itself by the production of the diffuse flux of