A new anti-neutrino detection technique based on positronium tagging with plastic scintillators

作者：Consolati G; Franco D^*; Jollet C; Meregaglia A; Minotti A; Perasso S; Tonazzo A

来源：Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment , 2015, 795: 364-369.

DOI：10.1016/j.nima.2015.06.021

• Neutrino
• Reactor
• Posittonium
• Detector

The main signature for anti-neutrino detection in reactor and geo-neutrino experiments based on scintillators is provided by the space-time coincidence of positron and neutron produced in the Inverse Beta Decay reaction. Such a signature strongly suppresses backgrounds and allows for measurements performed underground with a relatively high signal-to-background ratio. In an aboveground environment, however, the twofold coincidence technique is not sufficient to efficiently reject the high background rate induced by cosmogenic events. Enhancing the positron-neutron twofold coincidence efficiency may pave the way to future aboveground detectors for reactor monitoring. We propose a new detection scheme based on a threefold coincidence, among the positron ionization, the ortho-positronium (o-Ps) decay, and the neutron capture, in a sandwich detector with alternated layers of plastic scintillator and aerogel powder. We present the results of a set of dedicated measurements on the achievable light yield and on the o-Ps formation and lifetime. The efficiencies for signal detection and background rejection of a preliminary detector design are also discussed.

• 出版日期2015-9-21
• 单位中国地震局