PT Journal
AU NEXT Collaboration (McDonald, ADea
   Alvarez, V
   Benlloch-Rodriguez, JM
   Carcel, S
   Carrion, JV
   Diaz, J
   Felkai, R
   Herrero, P
   Kekic, M
   Lopez-March, N
   Martinez-Lema, G
   Muñoz Vidal, J
   Novella, P
   Palmeiro, B
   Perez, J
   Querol, M
   Renner, J
   Romo-Luque, C
   Sorel, M
   Uson, A
   Yahlali, N
TI Electron drift and longitudinal diffusion in high pressure xenon-helium gas mixtures
SO Journal of Instrumentation
JI J. Instrum.
PY 2019
BP P08009 - 19pp
VL 14
DI 10.1088/1748-0221/14/08/P08009
LA English
DE Charge transport and multiplication in gas; Gaseous imaging and tracking detectors
AB We report new measurements of the drift velocity and longitudinal diffusion coefficients of electrons in pure xenon gas and in xenon-helium gas mixtures at 1-9 bar and electric field strengths of 50-300 V/cm. In pure xenon we find excellent agreement with world data at all E/P, for both drift velocity and diffusion coefficients. However, a larger value of the longitudinal diffusion coefficient than theoretical predictions is found at low E/P in pure xenon, below the range of reduced fields usually probed by TPC experiments. A similar effect is observed in xenon-helium gas mixtures at somewhat larger E/P. Drift velocities in xenon-helium mixtures are found to be theoretically well predicted. Although longitudinal diffusion in xenon-helium mixtures is found to be larger than anticipated, extrapolation based on the measured longitudinal diffusion coefficients suggest that the use of helium additives to reduce transverse diffusion in xenon gas remains a promising prospect.
ER