Acceleration of cosmic rays in astrophysical jets is investigated. Particles are accelerated at the outer bow shock and by shear flows in the jet cocoon. Applications for the origin and chemical ...composition of ultra-high-energy cosmic rays are discussed.
We investigate acceleration of cosmic rays by shocks and accretion flows in galaxy clusters. Numerical results for spectra of accelerated particles and nonthermal emission are presented. It is shown ...that the acceleration of protons and nuclei in the nearby galaxy cluster Virgo can explain the observed spectra of ultra high energy cosmic rays.
The Tunka-133 EAS Cherenkov light array: Status of 2011 Berezhnev, S.F.; Besson, D.; Budnev, N.M. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
11/2012, Letnik:
692
Journal Article
Recenzirano
Odprti dostop
A new EAS Cherenkov light array, Tunka-133, with ∼1km2 geometrical area has been installed at the Tunka Valley (50km from Lake Baikal) in 2009. The array permits a detailed study of cosmic ray energy ...spectrum and mass composition in the energy range 1016–1018eV with a uniform method. We describe the array construction, DAQ and methods of the array calibration. The method of energy reconstruction and absolute calibration of measurements are discussed. The analysis of spatial and time structure of EAS Cherenkov light allows to estimate the depth of the EAS maximum Xmax.
The results on the all particles energy spectrum and the mean depth of the EAS maximum Xmax vs. primary energy derived from the data of two winter seasons (2009–2011) are presented. Preliminary results of joint operation of the Cherenkov array with antennas for the detection of EAS radio signals are shown. Plans for future upgrades – deployment of remote clusters, radioantennas and a scintillator detector network and a prototype of the HiSCORE gamma-telescope – are discussed.
Cosmic ray acceleration by astrophysical shocks in supernova remnants is briefly reviewed. Results of numerical modeling taking into account magnetic field amplification by streaming instability and ...shock modification are presented. Nonthermal emission produced by accelerated particles in young and old supernova remnants is compared with available data of radio, X-ray, and gamma-ray astronomy. We also discuss a possibility of particle acceleration to PeV energies at supernova shocks propagating in the interstellar bubbles created by stellar winds of supernova progenitors.
We have studied the nonresonant streaming instability of charged energetic particles moving through a background plasma, discovered by Bell. We confirm his numerical results regarding a significant ...magnetic field amplification in the system. A detailed physical picture of the instability development and of the magnetic field evolution is given.
The propagation of ultrahigh-energy cosmic rays from nearby sources is studied. It is shown that the spectrum, chemical composition, and anisotropy observed at energies above 5 × 10
18
eV can be ...explained within the model of one nearby galaxy (M87) if the source is strongly enriched with heavy nuclei.
A study is performed of the acceleration of cosmic rays by shock waves propagating in bubbles of hot rarefied gas created by the stellar wind of supernova progenitors. Spectra of accelerated ...particles produced in type Ib/c supernova remnants are determined.
The transport equation for cosmic rays in the Galaxy is solved simultaneously with equation for energy density of magnetohydrodynamic turbulence. The obtained spectra of cosmic ray nuclei with ...energies 10
5
to 10
11
eV are consistent with observational data, including the peak in the ratio of secondary to primary nuclei fluxes at around 1 GeV/nucleon.
A nonlinear model of cosmic-ray acceleration at the shock fronts in the supernova remnants W28, W44, and IC433 is investigated. The hydrodynamic evolution of a supernova remnant, including the shock ...modification by the pressure of accelerated particles and the streaming instability of particles upstream of the shock propagating in a partially ionized interstellar gas, is modeled. The electromagnetic radiation generated by accelerated particles is calculated and compared with observations in a wide range of photon energies.
PDF
