相关论文: On soil activation by cosmic rays at different alt…
The long-held notion that the highest-energy cosmic rays are of distant extragalactic origin is challenged by observations that events above $\sim 10^{20}$ eV do not exhibit the expected high-energy cutoff from photopion production off the…
We show that the flux of the high-energy cosmic ray positrons observed near Earth is that expected from the decay of mesons produced by the primary cosmic rays (CRs) in the local interstellar medium.
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…
The photo-disintegration of cosmic ray nuclei by starlight leads to the production of secondary antineutrinos. We have assumed that the flux of the ultrahigh energy cosmic ray nuclei near the Galactic plane region is the same as that…
We introduce neutrino astronomy starting from the observational fact that Nature accelerates protons and photons to energies in excess of 10^{20} and 10^{13} eV, respectively. Although the discovery of cosmic rays dates back a century, we…
We perform Monte Carlo simulations of cosmic ray-induced hard X-ray radiation from the Earth's atmosphere. We find that the shape of the spectrum emergent from the atmosphere in the energy range 25-300 keV is mainly determined by Compton…
Neutrons can induce background events in underground experiments looking for rare processes. Neutrons in a MeV range are produced in radioactive decays via spontaneous fission and (alpha, n) reactions, and by cosmic rays. Neutron fluxes…
In order to optimise the design of space instruments making use of detection materials with low atomic numbers, an understanding of the atmospheric neutron environment and its dependencies on time and position is needed. To produce a simple…
Cosmic radiation backgrounds are a constraint on life, and their distribution will affect the Galactic Habitable Zone. Life on Earth has developed in the context of these backgrounds, and characterizing event rates will elaborate the…
The collision of a high energy cosmic ray with a nucleon in the upper atmosphere could produce long-lived heavy particles. Such particles would be very penetrating, since the energy loss in matter scales as the inverse mass, and could reach…
Cosmic ray flux in our planetary system is primarily modulated by solar activity. Radiation effects of cosmic rays on the Earth strongly depend on latitude due to the variation of the geomagnetic field strength. To study these effects we…
Cosmic-ray neutron probes are widely used to monitor environmental water content near the surface. The method averages over tens of hectares and is unrivaled in serving representative data for agriculture and hydrological models at the…
We consider the possibility that the particles in the Ultra High Energy Cosmic Rays arriving to Earth might be neutrons instead of protons. We stress that in such case the argument for the GZK cutoff is weaker and that it is conceivable…
The center of the our Galaxy is a region where very energetic phenomena take place. In particular powerful cosmic ray sources can be located in that region. The cosmic rays accelerated in these sources may interact with ambient protons…
Higher concentrations of atmospheric nitrous oxide (N2O) are expected to slightly warm Earth's surface because of increases in radiative forcing. Radiative forcing is the difference in the net upward thermal radiation flux from the Earth…
The atmospheric secondary antiproton flux is studied for detection altitudes extending from sea level up to about 3 earth radii, by means of a 3-dimensional Monte-Carlo simulation, successfully applied previously on other satellite and…
(abridged abstract) Theoretical arguments indicate that close-in terrestial exoplanets may have weak magnetic fields. As described in the companion article (Paper I), a weak magnetic field results in a high flux of galactic cosmic rays to…
Cosmic rays produce molecular cluster ions as they pass through the lower atmosphere. Neutral molecular clusters such as dimers and complexes are expected to make a small contribution to the radiative balance, but atmospheric absorption by…
Recent astronomical observations reveal that Active Galactic Nuclei (AGN) are sources of high-energy radiation. For example, the Fermi-LAT and Hess telescopes have detected gamma-ray emissions from the cores of several types of AGN's. Even…
The supernova explosion which deposited $^{60}$Fe isotopes on Earth 2-3 million years ago should have also produced cosmic rays which contribute to the locally observed cosmic ray flux. We show that the contribution of this "local source"…