We consider propagation of nuclei with energies over 10
18
eV in the expanding Universe filled with background electromagnetic radiation. The spectrum of sources of extragalactic cosmic rays for ...protons and nuclei up to iron is determined on the basis of the particle spectrum observed near Earth as a solution of the inverse problem of transfer of ultrarelativistic nuclei. The method of regularization of the solution of this mathematically ill-posed problem is used basing on the data of the Pierre Auger Observatory on the energy spectrum of cosmic rays, the average logarithm of the mass number, and its variance. The found energy spectra of the sources prove to be very hard and strongly dependent on the assumption about the composition of the accelerated nuclei.
The energy spectra of extragalactic sources of cosmic rays are calculated by solving an inverse problem of the transport of cosmic rays with energies of 10
18
–10
21
eV in a Universe filled with ...background electromagnetic radiation. Calculations are performed using cosmic-ray spectra measured on Earth in Auger experiments. It is assumed that protons and iron nuclei dominate in the composition of a source.
Propagation of ultra-high energy nuclei in expending universe filled with background radiation is considered. We developed numerical code for solution of inverse problem for cosmic-ray transport ...equation that allows determination of source spectrum from the spectrum observed at the Earth. The injection spectra of protons and iron nuclei in extragalactic sources are found assuming that these species dominate in the source composition. Data from the Auger and Telescope Array experiments are used to illustrate the method.
It is shown that the acceleration of particles by a powerful relativistic jet associated with the activity of a supermassive black hole in the Galactic center several million years ago may explain ...the observed cosmic ray spectrum at energies higher than \(10^{15}\) eV. The accelerated particles are efficiently confined in the extended magnetized gas halo created by the supernova and central black hole activity just after the Galaxy formation. We found that both the heavy and light chemical composition of ultra-high energy cosmic rays can be consistent with observations.
The propagation of ultrahigh-energy nuclei in an expanding Universe filled with background electromagnetic radiation is considered. A numerical method for solving the inverse problem for the equation ...of cosmic-ray transport is developed that allows the spectrum of sources to be determined from the cosmic-ray spectrum observed near the Earth. The spectra of injected protons and nuclei in extragalactic sources are found by assuming that they are functions of the magnetic rigidity of particles. The data from observations obtained in the Auger experiment are used.
The propagation of ultrahigh energy nuclei in an expanding universe filled with background electromagnetic radiation is considered. A numerical method for solving the inverse problem for the equation ...of cosmic ray transport is developed. The method allows us to determine a source spectrum from the cosmic ray spectrum observed near Earth. The spectra of injected protons and nuclei of iron were found in extragalactic sources under the assumption that these types of particles predominate in the composition of the sources. The method of calculation is illustrated using observational data obtained in the Auger and Telescope Array experiments.
It is shown that the relativistic jets associated with the growth and past activity of the supermassive black hole in the Andromeda galaxy could be the main source of cosmic rays with energies above ...\(10^{15}\) eV. Most of the cosmic ray energy is related to a bow shock of the jet that produces multi-PeV cosmic rays with light composition. The highest energy cosmic rays with heavy composition are produced in the jet itself. The spectra of energetic particles produced in Andromeda galaxy and propagated to the Earth are calculated and compared with observations.
A numerical code is described that simulates the propagation of protons and ultrahigh-energy nuclei in an expanding Universe, taking into account the interaction with the background electromagnetic ...radiation. Using this code, we calculate the intensity of extragalactic cosmic rays, sources of which are jets of galaxies with active nuclei.
Acceleration of protons and nuclei by shock waves arising during accretion on galaxy clusters is considered. The generation of magnetohydrodynamic turbulence by streaming instability of accelerated ...particles in a shock precursor, cluster mass distribution, and particle energy loss upon interaction with cosmic microwave background and IR background radiation are taken into account. The contribution of these sources to the cosmic ray intensity observed at energies of 10
17
–10
20
eV is calculated.
Amplification of the magnetic field in young supernova remnants leads to the corresponding increase in the maximum energy of particles approximately to the knee energy 3 × 1015 eV at the end of the ...free expansion stage. The knee in the spectrum of cosmic rays is due to the transition of the supernova remnant from the free expansion stage to the Sedov stage. The knee energy is calculated for different types of supernovae. The maximum energy of accelerated particles teaches Z × 1017 eV for the observed remnant expansion velocities.