Related papers: An anti-knee
The diffuse $\gamma$-ray emission was measured up to $957$ TeV by the Tibet-AS$\gamma$ experiment recently. Assuming that it is produced by the hadronic interaction between cosmic ray nuclei and the interstellar medium, it requires that the…
More than fifty years after the discovery of the knee in the cosmic ray spectra, its physical origin remains a mystery. This is partly due to the ambiguity of the energy spectrum of individual composition. Recently, direct measurements from…
The knee of cosmic ray spectra reflects the maximum energy accelerated by galactic cosmic ray sources or the limit to the ability of galaxy to bind cosmic rays. The measuring of individual energy spectra is a crucial tool to ascertain the…
The existence of the spectral break around $\sim 3 \times 10^{15}$ eV in the cosmic ray spectrum (referred to as the `knee') is one of the biggest questions in cosmic ray astrophysics. At the same time, the origin of cosmic rays above the…
Two structures in the all-particle energy spectrum of cosmic rays, the knee at 4 PeV and the second knee around 400 PeV are proposed to be explained by a phenomenological model, the poly gonato model, connecting direct and indirect…
The knee phenomenon of the cosmic ray spectrum, which plays an important role in studying the acceleration mechanism of cosmic rays, is still an unsolved mystery. We try to reconcile the knee spectra measured by ARGO-YBJ and Tibet-III. A…
We report the observation of a steepening in the cosmic ray energy spectrum of heavy primary particles at about $8 \times 10^{16}$ eV. This structure is also seen in the all-particle energy spectrum, but is less significant. Whereas the…
We note that antishadowing could help in the explanation of cosmic rays phenomena such as knee in the energetic spectrum and existence of penetrating and long-flying particles.
The differential energy spectrum of the cosmic radiation from solar modulation energies up to 5x10**19 eV is correctly predicted by a recent theory of the knee and ankle which uses only one normalization point. This remarkable quantitative…
The measurement of cosmic ray energy spectra, in particular for individual species, is an essential approach in finding their origin. Locating the "knees" of the spectra is an important part of the approach and has yet to be achieved. Here…
The knee-like structure around 4 PeV is the most striking feature in the cosmic ray energy spectrum, whose origin remains enigmatic. We propose a novel concept of the total logarithmic mass energy spectrum to characterize the knee, taking…
The small change in the spectral slope of the overall intensity of cosmic rays near 1 PeV may be associated with the endpoint energy of supernova shock acceleration. A crucial test of this connection and other ideas of the origin of the…
It is shown that the fine stucture of the cosmic ray energy spectrum in the knee region, if explained by the Single Source Model (SSM), can, in principle, be clearly revealed and magnified in the size spectrum of extensive air showers (EAS)…
The differential intensity of cosmic radiation shows a sequence of depressions referred to as "knees" in a large energy band above 10^15 eV. The global depression entailed in the complete spectrum with respect to the extrapolated intensity…
Data obtained in the ATIC-2 (Advanced Thin Ionization Calorimeter), CREAM (Cosmic Ray Energetics and Mass)) and PAMELA (Payload for Antimatter Matter Exploration and Light-nuclei Astrophysics) experiments suggest that elemental interstellar…
The energies of cosmic rays, fully ionized charged nuclei, extend over a wide range up to 10^20 eV. A particularly interesting energy region spans from 10^14 to 10^18 eV, where the all-particle energy spectrum exhibits two interesting…
In this work we examine with the help of Monte Carlo simulation whether a consistent primary energy spectrum of cosmic rays emerges from both the experimentally observed total charged particles and muon size spectra of cosmic ray extensive…
In the last few years several experiments have shown that the cosmic ray spectrum below the knee is not a perfect power-law. In particular, the proton and helium spectra show a spectral hardening by ~ 0.1-0.2 in spectral index at particle…
Nonlinear kinetic theory of cosmic ray (CR) acceleration in supernova remnants is employed to calculate CR spectra. The magnetic field in SNRs is assumed to be significantly amplified by the efficiently accelerating nuclear CR component. It…
The possibility of estimating the mass composition of primary cosmic rays above the knee of its energy spectrum through the study of high energy gamma rays, muons and neutrinos produced in the interactions of cosmic rays with the solar…