# Plastic scintillator detector with the readout based on an array of large-area SiPMs for the ND280/T2K upgrade and SHiP experiments

## TL;DR

This paper explores replacing traditional photomultiplier tubes with large-area SiPM arrays in plastic scintillator detectors, enhancing compactness, robustness, and performance for particle physics experiments like ND280/T2K and SHiP.

## Contribution

It demonstrates the feasibility and advantages of directly coupling large-area SiPM arrays to scintillators, replacing PMTs in large-scale detectors.

## Key findings

- Successful coupling of SiPM arrays to long scintillator bars.
- Improved timing performance in test-beam studies.
- Potential for compact, robust, and efficient detector designs.

## Abstract

Plastic scintillator detectors have been extensively used in particle physics experiments for decades. A large-scale detector is typically arranged as an array of staggered long bars which provide a fast trigger signal and/or particle identification via time-of-flight measurements. Scintillation light is collected by photosensors coupled to both ends of every bar. In this article, we present our study on a direct replacement of commonly used vacuum photomultiplier tubes (PMTs) by arrays of large-area silicon photomultipliers (SiPMs). An SiPM array which is directly coupled to the scintillator bulk, has a clear advantage with respect to a PMT: compactness, mechanical robustness, high PDE, low operation voltage, insensitivity to magnetic field, low material budget, possibility to omit light-guides. In this study, arrays of eight 6 x 6 mm2 area SiPMs were coupled to the ends of plastic scintillator bars with 1.68 m and 2.3 m lengths. An 8 channel SiPM anode readout ASIC (eMUSIC) was used for the readout, amplification and summation of signals of individual SiPMs. Timing characteristics of a large-scale detector prototype were studied in test-beams at the CERN PS. This technology is proposed for the ToF system of the ND280/T2K II upgrade at J-PARC and the timing detector of the SHiP experiment at the CERN SPS.