Fabrication of a Liquid Scintillator based on 7-Diethylamino-4-Methylcoumarin for Radiation Detection

Abstract

Organic scintillation detectors are widely used to measure the presence or absence of radiation. With these devices, there are advantages in that they are easy to manufacture, large in size, and have a short uorescence decay time. However, they are not suitable for gamma measurements because they are composed of a low-atomic-number material. In this regard, alternative materials for the secondary solute used in basic organic scintillators have been investigated, and the applicability of alternative materials, the detection characteristics, and neutron/gamma identi cation tests were all assessed. 7-Diethylamino-4-methylcoumarin (DMC), selected as an alternative material, is a benzopyrone derivative in the form of colorless crystals with high uorescence, a high quantum yield in the visible region, and excellent light stability. In addition, it has a large Stokes shift, and solubility in a solvent is good. Through an analysis in this study, it was found that the absorption wavelength range of DMC coincides with the emission wavelength range of PPO, which is the primary solute used with DMC. Finally, it was con rmed that the optimal concentration of DMC was 0.08 wt%. As a result of performing gamma and neutron measurement tests using a DMC-based liquid scintillator, it was found to perform well (FOM = 1.42) compared to a commercial liquid scintillator, BC501A.