July 29, 2022 Dataset Restricted Access

Data: Study of a possible silicon photomultiplier based readout of the large plastic scintillator neutron detector NeuLAND

Hensel, Thomas; Weinberger, David; Bemmerer, Daniel; Boretzky, Konstanze; Gasparic, Igor; Stach, Daniel; Wagner, Andreas; Zuber, Kai

The NeuLAND (New Large-Area Neutron Detector) plastic scintillator based time of flight detector for 0.2-1.6 GeV
neutrons is currently under construction at the Facility for Antiproton and Ion Research (FAIR), Darmstadt, Germany.
In its final configuration, NeuLAND will consist of 3,000 2.7 m long plastic scintillator bars that are read out on each
end by fast timing photomultipliers.
Here, data from a comprehensive study of an alternative light readout scheme using silicon photomultipliers (SiPM)
are reported.  For this purpose, a typical NeuLAND bar was instrumented on each end with a prototype of the same
geometry as a 1” photomultiplier tube, including four 6×6 mm2 SiPMs, amplifiers, high voltage supply, and micro-
controller.
Tests were carried out using the 35 MeV electron beam from the ELBE superconducting linac with its ps-level time jitter in two different modes of operation, namely parasitic mode with one electron per bunch and single-usermode with 1-60 electrons per bunch, using Acqiris fast digitizers. In addition, offline tests using cosmic rays and the NeuLAND data acquisition scheme were carried out.
Typical time resolutions of σ≤120 ps were found for ≥ 95% efficiency, improving on previous work at ELBE and exceeding the NeuLAND timing goal of σ <150 ps. Over a range of 10-300 MeV deposited energy in the NeuLAND bar,  the  gain  was  found  to  deviate  by ≤ 10%  (≤20%)  from  linearity  for  35μm  (75μm)  SiPM  pitch,  respectively, satisfactory for calorimetric use of the full NeuLAND detector.  The dark rate of the prototype studied was found to
be 70-200 s-1, comparable with the unavoidable cosmic-ray induced background.

The dataset contains the with the Acqiris Digitzier recorded waveforms and analysis scripts for interpretation of the data. Also GEANT4 simulations of the light propagation in a NeuLAND bar and the electron beam propagation are included.