Fluorescence time profile measurement of LAB based liquid scintillator in response to medium relativistic ion particles

TL;DR

This paper presents a novel measurement of fluorescence timing in LAB-based liquid scintillators responding to high-energy ions, revealing a clear $dE/dX$ dependence crucial for particle detection and physics research.

Contribution

It introduces the first measurement of fluorescence time properties of LAB scintillator with high-energy ions, expanding understanding beyond radioactive sources.

Findings

Observed a distinct $dE/dX$ dependence in fluorescence timing.

Compared results with radioactive sources showing consistent differences.

Results are vital for neutrino detection and scintillation mechanism understanding.

Abstract

Liquid scintillator is widely used in particle physics experiments due to its high light yield, good timing resolution, scalability and low cost. Certain liquid scintillators exhibit pulse shape discrimination capabilities because of difference in fluorescence timing properties induced by different particles. Its fluoresence timing properties have been measured mostly for radioactive decay sources at MeV energies. We present a novel measurement of fluorescence time properties of LAB based liquid scintillator in response to high-energy ions of hydrogen (Z = 1), helium (Z = 2) and Krypton at around 200-300 MeV/u for the first time. We compared the results to those from radioactive sources and observed a distinct $dE/dX$ dependence, regardless of the particle type. These findings are essential for physics searches such as the diffuse supernova neutrino background in large liquid scintillator detectors like JUNO, and are also critical towards understanding the underlying scintillation timing mechanism.