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A new model of cosmogenic tritium ($^3$H) production in the atmosphere is presented. The model belongs to the CRAC (Cosmic-Ray Atmospheric Cascade) family and is named as CRAC:3H. It is based on a full Monte-Carlo simulation of the cosmic-ray induced atmospheric cascade using the Geant4 toolkit. The CRAC:3H model is able, for the first time, to compute tritium production at any location and time, for any given energy spectrum of the primary incident cosmic ray particles, explicitly treating, also for the first time, particles heavier than protons. This model provides a useful tool for the use of $^3$H as a tracer of atmospheric and hydrological circulation. A numerical recipe for practical use of the model is appended.
We present the results of full new calculation of radiocarbon 14C production in the Earth atmosphere, using a numerical Monte-Carlo model. We provide, for the first time, a tabulated 14C yield function for the energy of primary cosmic ray particles r
The direct detection of dark matter particles requires ultra-low background conditions at energies below a few tens of keV. Radioactive isotopes are produced via cosmogenic activation in detectors and other materials and those isotopes constitute a b
Future direct searches for low-mass dark matter particles with germanium detectors, such as SuperCDMS SNOLAB, are expected to be limited by backgrounds from radioactive isotopes activated by cosmogenic radiation inside the germanium. There are limite
Tangential YORP, or TYORP, has recently been demonstrated to be an important factor in the evolution of an asteroids rotation state. It is complementary to normal YORP, or NYORP, which used to be considered previously. While NYORP is produced by non-
The precise location of the water ice condensation front (snow line) in the protosolar nebula has been a debate for a long time. Its importance stems from the expected substantial jump in the abundance of solids beyond the snow line, which is conduci