Liquid Argon test of the ARAPUCA device

TL;DR

This paper reports the experimental testing of the ARAPUCA device in liquid argon, demonstrating its photon detection efficiency and validating its design for use in neutrino experiments like DUNE.

Contribution

First experimental demonstration of the ARAPUCA device's effectiveness in liquid argon for neutrino detection applications.

Findings

Detection efficiency of 1.15% with experimental validation

Good agreement between measurements and Monte Carlo simulations

Prototype development and initial testing inside protoDUNE detector

Abstract

The ARAPUCA is a novel concept for liquid argon scintillation light detection which has been proposed for the photon detection system of the Deep Underground Neutrino Experiment. The test in liquid argon of one of the first ARAPUCA prototypes is presented in this work, where the working principle is experimentally demonstrated. The prototype has an acceptance window of 9 cm$^2$ and is read-out by a single SiPM with active area of 0.36 cm$^2$. Its global detection efficiency was estimated by exposing it to a $^{238}U$ $\alpha$ source and to cosmic rays and was found to be 1.15\% $\pm$ 0.15\%, in good agreement with the prediction of a detailed Monte Carlo simulation of the device. Several other ARAPUCA prototypes of bigger dimensions and read-out by arrays of SiPMs have been built and are actually under test. In particular 32 ARAPUCA cells have been installed inside the protoDUNE detector, which is being assembled at CERN and will be operated in the second half of 2018.