ANR JCJC Project NuToPs


Electron antineutrinos are commonly detected in liquid scintillator experiments via inverse beta decay, by looking at the coincidence between the reaction products, neutron and positron. Prior to positron annihilation, an electron–positron pair may form a long mean life ortho-positronium (o-Ps) state. The induced distortion of the photoelectron time distribution may represent a new signature for tagging positrons, and hence antineutrinos.

In this project, we propose to develop a new pulse shape discrimination technique to tag positrons in liquid scintillators. Such a technique has a strong potential in enhancing the antineutrino signature for present neutrino oscillation and geo-neutrino experiments, and for future Mega-ton scale detectors and nuclear reactor monitoring devices.

In this framework, we intend to investigate the possibility to enhance the signature, by characterizing the o-Ps formation probability and lifetime in scintillators, and by studying their dependence on fluor and doper concentrations.

As direct application of the acquired results, we will provide a detector design, optimized for nuclear reactor monitoring, based on positronium tagging.


Project Summary

Team Members