Nuclear reactor safeguard, based on detection of electron antineutrino flux and energy spectrum, is of great interests to both administrative agencies such as International Atomic Energy Agency (IAEA) and neutrino community. A dominant reaction channel of such detection is inverse beta decay (IBD), for which discrimination of gamma against neutron is critical. In this study, pulse shape discrimination (PSD) is used over plastic scintillator, for its ease of detector assembly, no risk of leakage, and high chemical stability. Using 22Na and 137Cs radioactive sources to calibrate the energy response of the whole system (data acquisition and materials), EJ200 and EJ426 scintillator combination is used as the discrimination setup. The figure of merit (FOM) can reach 9.13 ± 0.01, and could be adopted to build a reactor neutrino safeguard detector. In addition, the PSD of two kinds of plastic scintillators were compared. The FOM of the EJ276 plastic scintillator can reach 1.35 ± 0.01 at the energy threshold of 1 MeV gamma equivalent in comparison to 0.96 ± 0.01 of UPS-113NG at the same energy threshold.

The Taishan Antineutrino Observatory (TAO or JUNO-TAO) is a satellite experiment of the Jiangmen Underground Neutrino Observatory (JUNO). Located near a reactor of the Taishan Nuclear Power Plant, TAO will measure the reactor antineutrino energy spectrum with an unprecedented energy resolution of $$<2\%$$ < 2 % at 1 MeV. Energy calibration is critical to achieve such a high energy resolution. Using the Automated Calibration Unit (ACU) and the Cable Loop System (CLS), multiple radioactive sources are deployed to various positions in the TAO detector for energy calibration. The residual non-uniformity can be controlled within 0.2%. The energy resolution degradation and energy bias caused by the residual non-uniformity can be controlled within 0.05% and 0.3%, respectively. The uncertainty of the non-linear energy response can be controlled within 0.6% with the radioactive sources of various energies, and could be further improved with cosmogenic $$^{12}{\textrm{B}}$$ 12 B which is produced by the interaction of cosmic muon in the liquid scintillator. The stability of other detector parameters, e.g., the gain of each Silicon Photo-multiplier, will be monitored with an ultraviolet LED calibration system.

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Muon veto is an important technique of many low background experiments. With the push in improving the sensitivity and statistics, the size of the detector for particle experiments has also been increasing. Therefore, there is a greater demand on the size of the muon veto system to efficiently identify muon events passing through the detector, minimizing the associated dead time of the target detector, and simultaneously fitting in the space requirements. In this paper, two designs of muon veto detectors composed of 200 cm×20 cm×2 cm plastic scintillator strip and a wavelength shifting(WLS) fiber coupled with SiPM, are tested. We use cosmic muons to examine the plastic scintillator along the length by scintillator cubes as probes and therefore measuring photoelectron numbers as a function of position. The design of layout-4 meets the needs of JUNO-TAO and is a compact and cheap candidate.