Search results for "Particle flux"
showing 2 items of 2 documents
A new approach for modeling dry deposition velocity of particles
2018
Abstract The dry deposition process is recognized as an important pathway among the various removal processes of pollutants in the atmosphere. In this field, there are several models reported in the literature useful to predict the dry deposition velocity of particles of different diameters but many of them are not capable of representing dry deposition phenomena for several categories of pollutants and deposition surfaces. Moreover, their applications is valid for specific conditions and if the data in that application meet all of the assumptions required of the data used to define the model. In this paper a new dry deposition velocity model based on an electrical analogy schema is propose…
Observation of the suppression of the flux of cosmic rays above 4x10^19eV
2008
The energy spectrum of cosmic rays above 2.5 × 10¹⁸ eV, derived from 20,000 events recorded at the Pierre Auger Observatory, is described. The spectral index γ of the particle flux, J ∝ E-γ, at energies between 4 × 10¹⁸ eV and 4 × 10¹⁹ eV is 2.69 ± 0.02(stat) ± 0.06(syst), steepening to 4.2 ± 0.4(stat) ± 0.06(syst) at higher energies. The hypothesis of a single power law is rejected with a significance greater than 6 standard deviations. The data are consistent with the prediction by Greisen and by Zatsepin and Kuz'min.