J-PARC Neutron Beam Line (BL05/NOP) for Fundamental Physics

Abstract

The standard model of particle physics is the most successful theory. Since, however, it cannot explain the generation process of the matter/antimatter in the universe and cannot unify the gravitational force, many scientists are going to solve the problem. The neutron, the smallest chargeless baryon, is a unique particle and used to investigate such researches. BL05/NOP is a beamline for fundamental physics experiments using novel neutron optics techniques. This beamline is divided into three branches by beam benders; Unpolarized beam branch provides most intense beam and equips a Doppler shifter to use ultra cold neutrons. Polarized beam branch provides larger polarized beam and equips a spin flip chopper. Low-divergence beam branch provides high luminosity beam. In this paper, specification of the beamline and each branch are introduced.