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arXiv · 0909.2965

Measurements of photoelectron extraction efficiency from CsI into mixtures of Ne with CH4, CF4, CO2 and N2

J. Escada·L. C. C. Coelho·T. H. V. T. Dias·J. A. M. Lopes·J. M. F. dos Santos·A. Breskin
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Abstract

Experimental measurements of the extraction efficiency f of the UV-induced photoelectrons emitted from a CsI photocathode into gas mixtures of Ne with CH4, CF4, CO2 and N2 are presented; they are compared with model-simulation results. Backscattering of low- energy photoelectrons emitted into noble gas is significantly reduced by the admixture of molecular gases, with direct impact on the effective quantum efficiency. Data are provided on the dependence of f on the type and concentration of the molecular gas in the mixtures and on the electric field.

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J. Escada, L. C. C. Coelho, T. H. V. T. Dias, J. A. M. Lopes, J. M. F. dos Santos, A. Breskin. 2009-09-16. Measurements of photoelectron extraction efficiency from CsI into mixtures of Ne with CH4, CF4, CO2 and N2. https://doi.org/10.1088/1748-0221/4/11/p11025

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