Development and mass production of a mixture of LAB- and DIN-based gadolinium-loaded liquid scintillator for the NEOS short-baseline neutrino experiment

A new experiment, called the NEutrino Oscillation at Short baseline (NEOS), is proposed on the site of Hanbit Reactors at Yonggwang, South Korea, to investigate a reactor antineutrino anomaly. The homogeneous NEOS detector having a 1000-l target volume was constructed and deployed at the tendon gallery 25 m away from the reactor core. The NEOS detector employs a linear alkylbenzene (LAB) based gadolinium loaded liquid scintillator with 10 % di-isopropylnaphthalene (DIN) based liquid scintillator to improve the particle identification via pulse shape discrimination. In this paper, we report the procedure for the mass production of the Gd-loaded scintillator for the NEOS detector.