The Study Of Neutrino Signal In Liquid Xenon Detector

Neutrino is one of the most basic particles that make up nature.Among the seventeen kinds of particles included in the standard model,three basic particles are neutrinos:?_e,?_?and?_?.Due to small mass,uncharged and penetrating properties,they are difficult to react with others and are difficult to be detected extremely.PandaX is a dark matter direct detection experiment with two-phase liquid xenon time projection chamber?TPC?technology.Neutrinos from the universe,the solar neutrinos especially,can also interact with xenon through coherent nuclear elastic scattering processes,electroweak processes,and possibly neutrino magnetic moments.Then they can generate nuclear recoil or electronic recoil signals in liquid xenon detection experiments.Therefore,in addition to detecting the dark matter,the PandaX experiment also has a strong sensitivity to the measurement of neutrinos in the universe.Besides,the supernova neutrino will escape from the supernova before the photon when a supernova burst.Therefore,people using particle detection can obtain information earlier than using optical detection.PandaX joins the Supernova Early Warning System?SNEWS?by the advantage of its neutrino detection,and is responsible for providing early warning of supernova burst.This article focuses on the number of signals generated by solar neutrino and supernova neutrino in liquid xenon detector.It is divided into the following steps:firstly,determine the flux of the neutrinos in the earth;secondly,determine the type of reaction that neutrinos can occur in the detector and the reflection cross section of each reaction types;finally,how many neutrinos will react in the detector can be calculated according to the flux of the neutrino on the earth and the reaction cross section,and the number of signals collected in the detector can be calculated by using the detection efficiency of the detector.The results show that in liquid xenon detector,the nuclear recoil signals caused by neutrinos are mainly derived from ⁸B neutrinos and hep neutrinos,while pp neutrinos and ⁷Be neutrinos are the main source of electronic recoil signals.The neutrino is expected to produce278 ton^-1year^-1 electronic recoil cases in the liquid xenon detector.In PandaX-4T detector,the nuclear recoil signal from neutrino is about 0.4 ton^-1year^-1,and it is expected to see 1 or 2signals during the two-year running time.If a supernova burst,it is expected that 10.7 signals will be seen in the PandaX-4T detector and all of them are from nuclear recoil reaction.