The Korean Physical Society 06130 22, Teheran-ro 7-gil, Gangnam-gu, Seoul, Republic of Korea 610 Representation : Tae Won NOH TEL: 02-556-4737 FAX: 02-554-1643 E-mail : Copyright(C) KPS, All rights reserved.
30 May 2022 to 4 June 2022
Virtual Seoul
Asia/Seoul timezone

Background measurements at Jingping Neutrino 1-t prototype

Not scheduled
Virtual Seoul

Virtual Seoul

Poster Solar neutrinos Poster


In 2017-2020, Jingping Neutrino 1-t prototype has detected numerous MeV radioactive background events, 343 high energy muon events and muon induced neutrons. By Bi-Po coincidence, the U238 contamination of liquid scintillator (LS) is measured as $(6.98 \pm 0.73) \times 10^{-13}$ g/g, and Th232 upperlimit is $3.7 \times 10^{-13}$ g/g (95% C.L., preliminary). On PMT glass, K40 contamination is $(5.73 \pm 0.79stat. \pm 1.49sys. ) \times 10^{-8}$ g/g and Tl208 event rate is $(3.86 \pm 0.26stat. \pm 0.85sys. ) \times 10^{-3}$ Bq/g, indicating $(2.64 \pm 0.18stat. \pm 0.58sys. ) \times 10^{-6} g/g$ Th232. The radioactivity of LS will be further suppressed after the distillation system is online. The muon flux is $(3.61 \pm 0.19stat. \pm 0.10sys.) \times 10^{-10} \mathrm{cm}^{-2}\mathrm{s}^{-1}$ with an average energy of 340 GeV, and its neutron yield is $(3.44 \pm 1.86stat. \pm 0.76syst.) \times 10^{-4}\mathrm{\mu}^{-1}\mathrm{g}^{-1}\mathrm{cm}^{2}$. Those results indicates that CJPL is an ideal place for low background experiments such as solar neutrino observatory. We are making steady progresses on lowering radioactive isotopes of detector materials.

Collaboration Jinping Neutrino Experiment

Primary author

Yiyang Wu (Tsinghua University)

Presentation Materials