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Negative Ion Drift and Diffusion in a TPC near 1 Bar

C. J. Martoff·R. Ayad·M. Katz-Hyman·G. Bonvicini·A. Schreiner
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Abstract

Drift velocity and longitudinal diffusion measurements are reported for a Negative Ion TPC (NITPC) operating with Helium + carbon disulfide gas mixtures at total pressures from 160 to 700 torr. Longitudinal diffusion at the thermal-limit was observed for drift fields up to at least 700 V/cm in all gas mixtures tested. The results are of particular interest in connection with mechanical simplification of Dark Matter searches such as DRIFT, and for high energy physics experiments in which a low-Z, low density, gaseous tracking detector with no appreciable Lorentz drift is needed for operation in very high magnetic fields.

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C. J. Martoff, R. Ayad, M. Katz-Hyman, G. Bonvicini, A. Schreiner. 2004-06-24. Negative Ion Drift and Diffusion in a TPC near 1 Bar. https://doi.org/10.1016/j.nima.2005.08.103

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