相关论文: Do we observe fluctuation of cross section in cosm…
Cosmic rays are often modeled as charged particles. This allows their non-ballistic propagation in magnetized structures to be captured. In certain situations, a neutral cosmic ray component can arise. For example, cosmic ray neutrons are…
It is presumed that the observed cosmic rays up to about $3\times 10^{18}$ eV are of Galactic origin, the particles being the ones which are found in the composition of the stellar winds of stars that explode as supernova into the…
High-energy cosmic ray electrons interaction with Dark Matter particles are considered. In particular, a weakening of energy spectrum of cosmic electrons is predicted resulting from inelastic electron scattering on hyper-pions in the…
The fraction of positrons and electrons in cosmic rays recently observed on the International Space Station unveiled an unexpected excess of the positrons, undermining the current foundations of cosmic rays sources. We provide a quantum…
Cosmic-ray antideuterons could be a key for the discovery of exotic phenomena in our Galaxy, such as dark-matter annihilations or primordial black hole evaporation. Unfortunately the theoretical predictions of the antideuteron flux at Earth…
Nonstandard neutrino properties (masses, mixing, sterile states, electromagnetic interactions, and so forth) can have far-reaching ramifications in astrophysics and cosmology. We look at the most interesting cases in the light of the…
A review of the status of the knowledge in the field of High-energy cosmic particles is presented. The spectrum, arrival direction distribution and composition measurements are summarized, together with some implications for the…
It is now widely acknowledged that cosmic rays experiments can test possible new physics directly generated at the Planck scale or at some other fundamental scale. By studying particle properties at energies far beyond the reach of any…
Cosmic ray story begins at the beginning of XX century. More then 100 years later, most of the main issues are still open questions, as sources, acceleration mechanism, propagation and composition. There is a continuing fascination with the…
Equations to investigate fluctuations in cosmic X-ray background radiation due to point-like sources at high-redshift are formulated in a systematic way. The angular power spectrum of X-ray background fluctuations is investigated from…
Some new developments obtained in the last few years concerning the propagation of high energy cosmic rays are discussed. In particular, it is shown how the inclusion of drift effects in the transport diffusion equations leads naturally to…
Contrary to expectations, several cosmic ray events with energies above $10^{20}$ eV have been observed. The flux of such events is well above the predicted Greisen-Zatsepin-Kuzmin cutoff due to the pion production (via the $\Delta$…
We have observed reproducible fluctuations of the Coulomb drag, both as a function of magnetic field and electron concentration, which are a manifestation of quantum interference of electrons in the layers. At low temperatures the…
Scattering of electromagnetic waves lies at the heart of most experimental techniques over nearly the entire electromagnetic spectrum, ranging from radio waves to optics and X-rays. Hence, deep insight into the basics of scattering theory…
Research in cosmic rays is now nearly a century old, but most of the fundamental questions in this field remain unanswered, on the other hand the perspectives of future studies in the next decade are very bright. New detectors will provide…
Cosmic ray propagation is diffusive because of pitch angle scattering by waves. We demonstrate that if the high-amplitude magnetohydrodynamic turbulence with $\tilde B/\langle B\rangle \sim 1$ is present on top of the mean field gradient,…
We study the evolution of cosmological perturbations in a non-singular bouncing cosmology with a bounce phase which has superimposed oscillations of the scale factor. We identify length scales for which the final spectrum of fluctuations…
Since more than a century we investigate cosmic particles coming from the Universe with the aim of understanding their nature, their origin and how they are accelerated. So far, cosmic rays have provided many impressive results, giving…
Cosmic rays are a fundamental source of ionization for molecular and diffuse clouds, influencing their chemical, thermal, and dynamical evolution. The amount of cosmic rays inside a cloud also determines the $\gamma$-ray flux produced by…
Energetic particles, traditionally called Cosmic Rays, were discovered nearly a hundred years ago, and their origin is still uncertain. Their main constituents are the normal nuclei as in the standard cosmic abundances of matter, with some…