Optimization of the JUNO liquid scintillator composition using a Daya Bay antineutrino detector

• Published in: Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment Vol. 988; p. 164823
• Main Authors: Anfimov, N., de André, J.P.A.M., Bordereau, C., Cabrera, A., Cerna, C., Chen, H.S., Chen, X.R., Chen, Y., Cheng, Y.P., Chuvashova, A., Clementi, C., Di Lorenzo, S. Conforti, Dal Corso, F., Deng, Z.Y., Depnering, W., Druillole, F., Dwyer, D.A., Fan, L., Gan, H.N., Giuliani, F., Gonchar, M., Gromov, M., Guardone, N., Gul, M., Guo, Z., Hackspacher, P., Hagner, C., Heinz, T., Hor, Y.K., Hu, B.Z., Huang, H.X., Huo, W.J., Hussain, S., Insolia, A., Jaffe, D.E., Jen, K.L., Ji, X.L., Ji, X.P., Jing, X.P., Khosonthongkee, K., Kinz, P., Krumshteyn, Z., Kruth, A., Lei, L., Li, H.L., Li, J.Q., Li, S.C., Li, S.F., Liang, H., Liu, H., Liu, M., Liu, Y., Ludhova, L., Luo, W.M., Martellini, C., Morozov, N., Napolitano, J., Paoloni, A., Pelliccia, N., Peng, J.C., Qiao, H., Rezinko, T., Romani, A., Roskovec, B., Ruan, X.C., Sawangwit, U., Settimo, M., Shi, G., Shi, Y.J., Songwadhana, J., Soonthornthum, B., Sotnikov, A., Stahl, A., Štefánik, D., Strati, V., Trzaska, W., Wang, C.H., Wang, J., Wang, N.Y., Wang, Y.F., Watcharangkool, A., Wei, W., Wu, D.R., Wysotzki, C., Xia, D.M., Xie, Z.Q., Yang, H., Yang, X.Y., Young, B.L., Yu, C.X., Yuan, Y., Zeng, Y.D., Zhang, G.Q., Zhang, Z.Y., Zhao, S.J., Zheng, H., Zhou, S., Zong, L., Zou, J.H.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01-02-2021
• Subjects: Light yield; Liquid scintillator; Neutrino; Light yield; Liquid scintillator; Neutrino
• ISSN: 0168-9002; 1872-9576
• DOI: 10.1016/j.nima.2020.164823

To maximize the light yield of the liquid scintillator (LS) for the Jiangmen Underground Neutrino Observatory (JUNO), a 20 t LS sample was produced in a pilot plant at Daya Bay. The optical properties of the new LS in various compositions were studied by replacing the gadolinium-loaded LS in one antineutrino detector. The concentrations of the fluor, PPO, and the wavelength shifter, bis-MSB, were increased in 12 steps from 0.5 g/L and <0.01 mg/L to 4 g/L and 13 mg/L, respectively. The numbers of total detected photoelectrons suggest that, with the optically purified solvent, the bis-MSB concentration does not need to be more than 4 mg/L. To bridge the one order of magnitude in the detector size difference between Daya Bay and JUNO, the Daya Bay data were used to tune the parameters of a newly developed optical model. Then, the model and tuned parameters were used in the JUNO simulation. This enabled to determine the optimal composition for the JUNO LS: purified solvent LAB with 2.5 g/L PPO, and 1 to 4 mg/L bis-MSB.