Related papers: Cosmic ray knee and new physics at the TeV scale
In models with extra dimensions the fundamental scale of gravity M_D could be of order TeV. In that case the interaction cross section between a cosmic proton of energy E and a dark matter particle \chi will grow fast with E for center of…
We discuss possible implications of a large interaction cross section between cosmic rays and dark matter particles due to new physics at the TeV scale. In particular, in models with extra dimensions and a low fundamental scale of gravity…
We propose that the knee in the cosmic ray spectrum at energies E ~ 10^{15.5} eV is due to "new physics", namely to a channel in the high energy (~ TeV in the CM) proton interactions hitherto unaccounted for in estimating the energies of…
We explore the possibility that a new physics interaction can provide an explanation for the knee just above $10^6$ GeV in the cosmic ray spectrum. We model the new physics modifications to the total proton-proton cross section with an…
We have proposed that the cosmic ray spectrum "knee", the steepening of the cosmic ray spectrum at energy $E \gsim 10^{15.5}$ eV, is due to "new physics", namely new interactions at TeV cm energies which produce particles undetected by the…
Spectra of Cosmic Rays (CRs), particularly their features, may hold essential information about astroparticle and fundamental physics. Realizing that both $4$ PeV CR knee and electron's TeV break have nearly identical Lorentz factor, i.e.…
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…
In the cosmic ray spectrum, there are two knees (abrupt changes of slopes) located around the energies $E_{th}=10^{15.5}$ eV and $10^{17.8}$ eV respectively. Based on the pioneering work by Kostelecky and Ehrlich, we ascribe the first knee…
Scenarios in which the knee of the cosmic ray spectrum depends on the particle rigidities usually predict that the cosmic ray composition becomes heavier above the knee and have associated a change in the spectral slope of each individual…
The nature of the knee in the all-particle spectrum of cosmic rays remains subject of much investigation, especially in the aftermath of recent measurements claiming the detection of a knee-like feature in the spectrum of the light…
The most recent experimental results on the cosmic ray composition and energy spectrum above 1 TeV are reviewed and discussed. All data agree on the presence of the so-called ``knee'' at an energy E(knee) = 3-4 PeV; the knee is seen in all…
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…
The origin of the knee in cosmic ray spectrum remains to be an unsolved fundamental problem. There are various kinds of models which predict different break positions and the compositions of the knee. In this work, we suggest to use diffuse…
The hypothesis that the electron neutrino is a tachyon with |m|=sqrt(-m^2) = 0.5 eV/c^2 is consistent with certain properties of the cosmic ray spectrum, including: the existence of a change in power law (the "knee") at E = 10^15 eV, the…
I develop a theory to account for the cosmic ray spectrum. The essential assumption is that, due to fast convective motions, the free mean path perpendicular to the magnetic field is independent of energy and has the scale of the thickness…
The search for a theory of the origin of cosmic rays that may be considered as a standard, agreeable model is still ongoing. On one hand, much circumstantial evidence exists of the fact that supernovae in our Galaxy play a crucial role in…
Cosmic rays around the so-called knee in the spectrum at around PeV primary energy are generally galactic in origin. Observations on the form of their energy spectrum and their mass composition are fundamental tools to understand the…
Recent observations of cosmic ray protons in the energy range $10^2$--$10^5$~GeV have revealed that the spectrum cannot be described by a simple power law. A hardening of the spectrum around an energy of order few hundred~GeV, first…
Cosmic rays around the knee are generally believed to be of galactic origin. Observations on their energy spectrum and chemical composition are important for understanding the acceleration and propagation of these cosmic rays. In addition,…
New physics beyond the electroweak scale may increase weak interaction cross sections beyond the Standard Model predictions. Such cross sections can be expected within theories that solve the hierarchy problem of known interactions with a…