R&D of water-based liquid scintillator with Gd as a reactor anti-neutrino monitor

作为IAEA（International Atomic Energy Agency）保障用反应堆中微子监测器，开发了不易燃、不挥发的钆（Gd）水基液体闪烁体。使用表面活性剂或市售纯皂将发光剂（PPO）溶于水中，利用钴60的γ射线的康普顿边缘电子测量光产额。在70%水+30%表面活性剂（SDS）+30g/L发光剂（PPO）+0.2%Gd的液体闪烁体中，光产额为9.55 ± 0.38 [pe]，是有机物基液体闪烁体的1/30。在50%水+50%商业纯皂+30g/L发光剂（PPO）的液体闪烁体中，光产额为6.428 ± 0.074 [pe]。上述水基液体闪烁体一年未出现老化。

As a reactor neutrino monitor for the safeguards of IAEA (International Atomic Energy Agency), the water-based liquid scintillator with gadolinium(Gd) which is nonflammable and nonvolatile was developed.The luminescence agent(PPO) was melted in water using a surface-active agent or commercial pure soap, and the light yield was measured using Compton edge electrons by gamma-rays from a cobalt 60. In the liquid scintillator of 70%water+30%surface-active agent(SDS)+30g/L luminescence agent(PPO)+0.2%Gd, the light yield was 9.55+-0.38 [pe] which is 1/30 of an organic matter based liquid scintillator. In the liquid scintillator of 50%water+50% commercial pure soap+30g/L luminescence agent(PPO), the light yield was 6.428+-0.074 [pe]. Aging of the water-based liquid scintillator mentioned above for one year was not appeared.