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arXiv · 1805.06367

Scintillation and Ionization Ratio of Liquid Argon for Electronic and Nuclear Recoils at Drift-Fields up to 3 kV/cm

T. Washimi·M. Kimura·M. Tanaka·K. Yorita
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Abstract

A two-phase argon detector has high discrimination power between electron recoil and nuclear recoil events based on the pulse shape discrimination and the ionization/scintillation ratio (S2/S1). This character is very suitable for the dark matter search to establish the low background experiment. However, the basic properties of S2/S1 of argon are not well known, as compared with xenon. We report the evaluation of S2/S1 properties with a two-phase detector at drift-fields of 0.2-3.0 kV/cm. Finally, the discrimination power against electron recoil background of S2/S1 is discussed.

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T. Washimi, M. Kimura, M. Tanaka, K. Yorita. 2018-09-26. Scintillation and Ionization Ratio of Liquid Argon for Electronic and Nuclear Recoils at Drift-Fields up to 3 kV/cm. https://doi.org/10.1016/j.nima.2018.09.019

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