Related papers: Cosmic ray knee and new physics at the TeV scale
An update of the status of the knee in the cosmic ray energy spectrum at 3-4 PeV is presented. We argue that the evidence in favour of the presence of a 'single source' is even stronger than before.
Galactic cosmic ray (CR) acceleration to the knee in the spectrum at a few PeV is only possible if the magnetic field ahead of a supernova remnant (SNR) shock is strongly amplified by CR escaping the SNR. A model formulated in terms of the…
Recently, LHAASO detected a gamma-ray emission extending beyond $100\,\rm{TeV}$ from 4 sources associated to powerful microquasars. We propose that such sources are the main Galactic PeVatrons and investigate their contribution to the…
It has recently been suggested that neutron stars inside the shells of young supernova remnants (SNR) are the sources of PeV cosmic rays and that the interaction of the particles with the radiation field in the SNR causes electron pair…
A TeV spectral break in the total flux of cosmic-ray electrons and positrons (CREs) at which the spectral power index softens from $\sim 3$ to $\sim 4$ has been observed by H.E.S.S. and recently confirmed by DAMPE with a high significance…
The energy at which cosmic rays from extra-galactic sources begin to dominate over those from galactic sources is an important open question in astroparticle physics. A natural candidate is the energy at the 'ankle' in the approximately…
If there are large extra dimensions and the fundamental Planck scale is at the TeV scale, then the question arises of whether ultra-high energy cosmic rays might probe them. We study the neutrino-nucleon cross section in these models. The…
Neutrino telescope IceCube has recently discovered astrophysical neutrinos with energies in the TeV-PeV range. We use the data of Fermi gamma-ray telescope to demonstrate that the neutrino signal has significant contribution from the Milky…
The paper discusses an approach that made it possible to estimate the distance to the nearest pevatrons, which form a knee in the spectrum of the cosmic ray nucleon component of about $4$ PeV. It is based on the spectra of nucleons and…
An overview on the present observational status and phenomenological understanding of cosmic rays above 10^16 eV is given. Above these energies the cosmic ray flux is expected to be gradually dominated by an extra-galactic component. In…
The paper investigates the overall and detailed features of cosmic ray (CR) spectra in the knee region using the scenario of nuclei-photon interactions around the acceleration sources. Young supernova remnants can be the physical realities…
The present paper deals with calculations based on a standard model of cosmic ray acceleration in Supernova remnants (SNR) and on the latest astronomical data concerning the variety in Supernovae types, energies as well as the sites of…
Primary cosmic ray particles above energies of about 100 TeV are investigated by large-area ground based detector installations, observing various components of the development of extensive air-showers (EAS). By such an indirect access to…
Suppose that even the highest energy cosmic rays (CRs) observed on Earth are protons accelerated in local Milky Way Galaxy sources, with few if any from more distant sources. In this paper we treat the problem that supernovae remnants…
Several kinds of measurements are combined in an attempt to obtain a consistent estimate of the spectrum and composition of the primary cosmic radiation through the knee region. Assuming that the knee is a signal of the high-energy end of a…
The observation of a small change in spectral slope, or 'knee' in the fluxes of cosmic rays near energies 10^15 eV has caused much speculation since its discovery over 40 years ago. The origin of this feature remains unknown. A small…
A brief motivation for studying cosmic rays at energies 10^14 < E < 10^17 eV is given. Besides astrophysical interests in identifying and understanding their sources, there are also particle physics aspects related to their transport…
The observed very high energy spectra of distant blazars are well described by secondary gamma rays produced in line-of-sight interactions of cosmic rays with background photons. In the absence of the cosmic-ray contribution, one would not…
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…
Recent observations show that the cosmic ray nuclei spectra start to harden above 100 GeV, in contradiction with the conventional steady-state cosmic ray model. We had suggested that this anomaly is due to the propagation effect of cosmic…