The JSNS\(^{2}\) (J-PARC Sterile Neutrino Search at J-PARC Spallation Neutron Source) experiment aims to search for neutrino oscillations over a 24\,m short baseline at J-PARC. The JSNS\(^{2}\) inner ...detector is filled with 17 tons of gadolinium-loaded liquid scintillator (LS) and both the intermediate \(\gamma\)-catcher and the optically separated outer veto are filled with un-loaded LS. Optical photons from scintillation are observed by 120 Photomultiplier Tubes (PMTs). A total of 130 PMTs for the JSNS2 experiment were both donated by other experiments and purchased from Hamamatsu. Donated PMTs were purchased around 10 years ago, therefore JSNS\(^{2}\) did pre-calibration of the PMTs including the purchased PMTs. 123 PMTs demonstrated acceptable performance for the JSNS\(^{2}\) experiment, and 120 PMTs were installed in the detector.
Ag-Cu nanocrystal mixture having the molar ratio of 1:1, 1:3, and 1:5 was prepared in thin film SiO
2 using the sol-gel method and high temperature heat treatment (500 °C). The high resolution TEM ...micrograph shows the particle size is distributed broadly covering 1–10 nm with the maximum at 4–5 nm. The absorption spectra were simulated using the bulk
Ag
Cu
dielectric constants by accommodating the nanocrystal size, and were compared with the measured absorption spectra. The third-order nonlinear optical properties of those nanocluster mixtures have been studied by the degenerate four wave mixing technique. The measured third-order nonlinear susceptibilities,
χ
(3), were on the order of 10
−8–10
−7 esu.
