Proposal: JSNS$^2$-II

• DOI: 10.48550/arxiv.2012.10807
• Publication Date: 2020-01-01
• Authors: S. Ajimura; M. Botran; J. H. Choi; Jeehye Choi; Myung-Ki Cheoun; T. Dodo; H. Furuta; J. Goh; Katsuhiro Haga; M. Harada; Shoichi Hasegawa; Y. Hino; T. Hiraiwa; H. I. Jang; Jinhyeok Jang; M. C. Jang; H. Jeon; S. H. Jeon; K. K. Joo; J. R. Jordan; D. EJung; S. Kang; Yoshimi Kasugai; T. Kawasaki; E. J. Kim; Jung-Hoon Kim; S. B. Kim; S. Y. Kim; W. Kim; T. Konno; Hidetaka Kinoshita; D. H. Lee; Sanghyun Lee; I. T. Lim; E. Marzec; T. Maruyama; S. Masuda; Shin-ichiro Meigo; Hideaki Monjushiro; D. H. Moon; T. Nakano; M. Niiyama; K. Nishikawa; M. Nomachi; M. Y. Pac; J. S. Park; S. J. M. Peeters; H. Ray; Gerrit Roellinghoff; C. Rott; K. Sakai; Shigeyasu Sakamoto; Tatsushi Shima; C. D. Shin; J. Spitz; I. Stancu; Y. Sugaya; F. Suekane; K. Suzuya; M. Taira; R. Ujiie; Y. Yamaguchi; M. Yeh; I. S. Yeo; Chang Geun Yoo; I. Yu; Adil Zohaib
• Keywords: Oscillation (cell signaling); J-PARC

This article describes the goal and expected sensitivity of JSNS$^2$-II experiment at J-PARC Materials Life Science Experimental Facility (MLF). The is second phase JSNS$^2$ (J-PARC Sterile Neutrino Search Spallation Neutron Source) with two detectors which are located in 24 m (an existing detector) 48 (new one) baselines to improve search for sterile neutrinos, especially low $Δm^2$ region, has been indicated by global fit appearance mode. new detector a similar structure as detector, already working. To compensate reduction neutrino flux due distance from mercury target, target mass Gd-loaded liquid scintillator Linear AlkylBenzene (LAB) based inside acrylic vessel 35 tons. keep same photo-coverage first we will surround 240 PMTs. With this experimental setup 5 years (times 1 MW beam power) exposure, significantly improved compared current JSNS$^2$, oscillation parameter region. can also confirm or refute most parameters' space preferred previous experiments 3 sigma C.L.. Considering these situations world wide status searches, eager start data taking configuration 2023. fund build was secured.