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arXiv · 1506.08748

Measurements of wavelength-dependent double photoelectron emission from single photons in VUV-sensitive photomultiplier tubes

C. H. Faham·V. M. Gehman·A. Currie·A. Dobi·P. Sorensen·R. J. Gaitskell
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Abstract

Measurements of double photoelectron emission (DPE) probabilities as a function of wavelength are reported for Hamamatsu R8778, R8520, and R11410 VUV-sensitive photomultiplier tubes (PMTs). In DPE, a single photon strikes the PMT photocathode and produces two photoelectrons instead of a single one. It was found that the fraction of detected photons that result in DPE emission is a function of the incident photon wavelength, and manifests itself below $\sim$250 nm. For the xenon scintillation wavelength of 175 nm, a DPE probability of 18--24\% was measured depending on the tube and measurement method. This wavelength-dependent single photon response has implications for the energy calibration and photon counting of current and future liquid xenon detectors such as LUX, LZ, XENON100/1T, Panda-X and XMASS.

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C. H. Faham, V. M. Gehman, A. Currie, A. Dobi, P. Sorensen, R. J. Gaitskell. 2015-06-29. Measurements of wavelength-dependent double photoelectron emission from single photons in VUV-sensitive photomultiplier tubes. https://doi.org/10.1088/1748-0221%2F2015%2F9%2Fp09010

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