<<<<<<<<<<<<<<<<<< CRC News 2023 年 5月24日 >>>>>>>>>>>>>>>>>>>> CRC 会員各位 CRC 事務局 ****** ****** Dear all, This is an announcement of the RCNP Colloquium by Dr. Akira KONAKA. Detailed information is as follows. ==================================================== Speaker: Dr. Akira KONAKA (TRIUMF, RCNP Osaka University, University of Victoria) Date: Tuesday, June 6 2023 Time: 16:00- (JST) Place: Lecture room 1 (H604) on the 6th floor of RCNP main building Zoom info: https://zoom.us/ Meeting ID: 946 6877 **** Passcode: ****** Title: Study of electron and muon quasi-elastic and pion production for neutrino cross section models Abstract: Precise neutrino oscillation measurements, such as CP violation measurement, require precise modelling of neutrino interaction on nuclei in the sub-GeV range. Charged lepton scattering is a promising way to constrain the challenging part of the models, such as spectral function, meson exchange current, and the final state interaction. By replacing the primary interaction from photon exchange with weak boson exchange, the charged lepton interaction study could be bridged to the neutrino interactions. A new Water Cherenkov detector Test Experiment (WCTE) at CERN is under preparation for a beam time in 2024. Sub-GeV secondary beam of electrons and muons are injected into a 4m-diameter water Cherenkov detector to study the detector response. In particular, the detector allows precise measurement of electron and muon quasi-elastic scattering and pion productions with 4π solid angle coverage. A new multi-index aerogel Cherenkov counters with the beam momenta tuned at the pion threshold, clean separation of muons from pions in the sub-GeV range is demonstrated for high statistics sub-GeV muon scattering measurement for the first time. Muon scattering suppresses radiative corrections and other higher-order electromagnetic processes, allowing a unique handle on the study of charged lepton interactions on nuclei. We will discuss the impact of the sub-GeV lepton scattering measurement and the status of the WCTE experiment at CERN. Contact: Tatsushi SHIMA shima at rcnp.osaka-u.ac.jp RCNP indico https://indico.rcnp.osaka-u.ac.jp/event/2142/