Analytical description of the time-over-threshold method based on the time properties of plastic scintillators equipped with silicon photomultipliers

TL;DR

This paper provides an analytical model of the signals from plastic scintillators with SiPMs using the ToT method, enabling improved time resolution for neutron detection in high-energy physics experiments.

Contribution

It introduces an analytical description of the ToT signals from plastic scintillators with SiPMs, facilitating slewing correction and enhancing timing accuracy.

Findings

Achieved 70 ps time resolution with the described method.

Established ToT-amplitude relationship for scintillator-SiPM signals.

Demonstrated the effectiveness of analytical modeling for detector timing improvements.

Abstract

A new high-granular compact time-of-flight neutron detector for the identification and energy measurement of neutrons produced in nucleus-nucleus interactions at the BM@N experiment, Dubna, Russia, at energies up to 4 AGeV is under development. The detector consists of approximately 2000 fast plastic scintillators, each with dimensions of 40$\times$40$\times$25 mm$^3$, equiped with SiPM (Silicon Photomultiplier) with an active area of 6$\times$6 mm$^2$. The signal readout from these scintillators will employ a single-threshold multichannel Time-to-Digital Converter (TDC) to measure their response time and amplitude using the time-over-threshold (ToT) method. This article focuses on the analytical description of the signals from the plastic scintillator detectors equipped with silicon photomultipliers. This description is crucial for establishing the ToT-amplitude relationship and implementing slewing correction techniques to improve the time resolution of the detector. The methodology presented in this paper demonstrates that a time resolution at the 70 ps level can be achieved for the fast plastic scintillator coupled with silicon photomultiplier with epitaxial quenching resistors.