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arXiv · 1508.07059

Measurement of Longitudinal Electron Diffusion in Liquid Argon

Yichen Li·Thomas Tsang·Craig Thorn·Xin Qian·Milind Diwan·Jyoti Joshi·Steve Kettell·William Morse·Triveni Rao·James Stewart·Wei Tang·Brett Viren
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Abstract

We report the measurement of longitudinal electron diffusion coefficients in liquid argon for electric fields between 100 and 2000 V/cm with a gold photocathode as a bright electron source. The measurement principle, apparatus, and data analysis are described. Our results, which are consistent with previous measurements in the region between 100 to 350 V/cm [1] , are systematically higher than the prediction of Atrazhev-Timoshkin[2], and represent the world's best measurement in the region between 350 to 2000 V/cm. The quantum efficiency of the gold photocathode, the drift velocity and longitudinal diffusion coefficients in gas argon are also presented.

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Yichen Li, Thomas Tsang, Craig Thorn, Xin Qian, Milind Diwan, Jyoti Joshi, Steve Kettell, William Morse, Triveni Rao, James Stewart, Wei Tang, Brett Viren. 2016-01-30. Measurement of Longitudinal Electron Diffusion in Liquid Argon. https://doi.org/10.1016/j.nima.2016.01.094

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