Performance of VUV-sensitive MPPC for Liquid Argon Scintillation Light

TL;DR

This paper evaluates a new VUV-sensitive MPPC's basic properties, temperature dependence, and photon detection efficiency for liquid argon scintillation light, highlighting its potential for dark matter detection applications.

Contribution

The paper provides the first detailed measurements of a VUV-sensitive MPPC's properties and efficiency at cryogenic temperatures, demonstrating its suitability for LAr detectors.

Findings

Photon detection efficiency estimated at 7% for 128 nm light.

Temperature dependence of breakdown voltage and dark count rate characterized.

Potential application in LAr-based dark matter detectors discussed.

Abstract

A new type of the Multi-Pixel Photon Counter (MPPC), sensitive to Vacuum Ultra-Violet (VUV) light (wavelength {\lambda} < 150 nm), is recently developed and produced by Hamamatsu Photonics K.K. The basic properties of the new MPPC are measured at cryogenic facility of Waseda university using liquid nitrogen. Temperature dependence of breakdown voltage, capacitance, and dark count rate of the MPPC are also evaluated. In addition, the absolute photon detection efficiency (PDE) for liquid argon (LAr) scintillation light ({\lambda} = 128 nm) is estimated to be about 7% with uncertainty of 2% by using 241 Am {\alpha}-ray source. Based on these basic measurements a possible application of the new MPPC to LAr detector for dark matter search is discussed.