Scintillator detectors with long WLS fibers and multi-pixel photodiodes

TL;DR

This study explores using Geiger mode multi-pixel photodiodes with long WLS fibers in scintillator bars for large volume neutrino detectors, demonstrating promising light yield results in prototype tests.

Contribution

It introduces a novel detector configuration combining long WLS fibers with multi-pixel photodiodes for large-scale neutrino experiments.

Findings

Minimum light yield of 7.2 p.e./MeV achieved

Prototype bars of 0.7 cm thickness tested

Effective readout with multi-pixel photodiodes demonstrated

Abstract

We have studied the possibility of using Geiger mode multi-pixel photodiodes to read out long scintillator bars with a single wavelength-shifting fiber embedded along the bar. This detector configuration can be used in large volume detectors in future long baseline neutrino oscillation experiments. Prototype bars of 0.7 cm thickness and different widths have been produced and tested using two types of multi-pixel photodiodes: MRS APD (CPTA, Moscow) and MPPC (Hamamatsu). A minimum light yield of 7.2 p.e./MeV was obtained for a 4 cm wide bar.