TY - JOUR AU - NEXT Collaboration (McDonald, A. D. et al AU - Alvarez, V. AU - Benlloch-Rodriguez, J. M. AU - Carcel, S. AU - Carrion, J. V. AU - Diaz, J. AU - Felkai, R. AU - Herrero, P. AU - Kekic, M. AU - Lopez-March, N. AU - Martinez-Lema, G. AU - Muñoz Vidal, J. AU - Novella, P. AU - Palmeiro, B. AU - Perez, J. AU - Querol, M. AU - Renner, J. AU - Romo-Luque, C. AU - Sorel, M. AU - Uson, A. AU - Yahlali, N. PY - 2019 DA - 2019// TI - Electron drift and longitudinal diffusion in high pressure xenon-helium gas mixtures T2 - J. Instrum. JO - Journal of Instrumentation SP - P08009 - 19pp VL - 14 PB - Iop Publishing Ltd KW - Charge transport and multiplication in gas KW - 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. SN - 1748-0221 UR - https://arxiv.org/abs/1902.05544 UR - https://doi.org/10.1088/1748-0221/14/08/P08009 DO - 10.1088/1748-0221/14/08/P08009 LA - English N1 - WOS:000482373600006 ID - NEXTCollaborationMcDonald_etal2019 ER -