Title :
Calculation of Drift Velocities and Diffusion Coefficients for Xe+ Ions in Gaseous Xe/3He Mixtures
Author :
Barata, J.A.S. ; Conde, C.A.N.
Author_Institution :
Univ. da Beira Interior, Covilha
fDate :
6/1/2007 12:00:00 AM
Abstract :
The drift velocities and the longitudinal and transverse diffusion coefficients for Xe+ ions in gaseous Xe/3He mixtures, at atmospheric pressures, for Xe concentrations between 1 and 30%, and reduced electric field strengths, from about 3 to 70 Td, corresponding to E/p, from about 1 to 22.5 V cm-1Torr-1 at 300 K, are calculated by simulation using a detailed Monte Carlo computer programme. This programme uses a set of integral and differential elastic collision cross sections for Xe ions with neutral He and Xe atoms, previously calculated by the authors using a modified Tang-Toennies ion-atom interaction potential and the JWKB approximation to calculate the phase shifts. The calculated drift velocities of Xe+ ions depend strongly on the concentration of Xe in the mixtures.
Keywords :
Monte Carlo methods; drift chambers; helium-3 counters; JWKB approximation; Monte Carlo computer programme; Xe-He - Binary; Xe/3He mixtures; diffusion coefficients; drift velocities; elastic collision cross sections; modified Tang-Toennies ion-atom interaction potential; phase shifts; positive Xe ions; temperature 300 K; Atmospheric modeling; Computational modeling; Computer simulation; Electron mobility; Frequency; Gases; Helium; Position sensitive particle detectors; Radiation detectors; Scattering; Atomic, molecular, ion, and heavy-particle collisions; Monte Carlo simulation; diffusion coefficients; ion mobility; kinetic and transport theory of gases;
Journal_Title :
Nuclear Science, IEEE Transactions on
DOI :
10.1109/TNS.2007.897821