超大发射度的高功率次级束流输运线研究

未来加速器中微子实验研究需要高功率的质子驱动器和高传输效率的pion和muon输运线。中国提出的muon衰变的中能中微子实验装置（MOMENT）要求能够传输超大横向发射度、能量范围从几个MeV到几百MeV的pion和muon束流，本项目着重研究pion和muon束流在大孔径高磁场超导螺线管组成的磁聚焦结构内传输的动力学机制，在此束流特点下，并解决几个关键的问题：1）接近5MW高能废质子束从高场螺线管的靶区引出方法； 2）次级粒子混合束的正负粒子高效分离技术；3）缩减次级粒子束的横向角散度的方法，通过减少次级粒子的角散增加远点探测器处的中微子流强；4）严格的本底要求需要研究降低中微子本底的方法；5）快速准确地计算中微子能谱；6）超过500kW的质子和中子束流进入pion衰变通道内，需要解决次级束流线中的屏蔽和束损问题。

The investigation of the future accelerator neutrino experiments requires the high-power proton driver and high-transport-efficiency pion and muon beam lines. The muon-decay medium baseline neutrino experiment facility (MOMENT) requires the pion and muon beam lines which can transport the beam with super large transverse emittance and energy range from several MeV to hundreds MeV. In this fund, ones will focus on the pion and muon beam dynamitic mechanism in the superconducting solenoid lattice with large aperture and high magnetic field. In the condition of these beam characteristics, several key problems must be solved: 1) The method of abstracting the almost 5MW waste proton beam from the target region composed with high-magnetic-field solenoids. 2) The technologies of high-efficiency charge separation for the secondary beam. 3) The method to reduce the secondary beam transverse divergence. It helps to increase the neutrino flux at the far detector by reducing the secondary particle angle divergence. 4) The rigorous background requires to study the method to reducing the neutrino background. 5) Calculating the neutrino energy spectra fast and precisely. 6) With more than 500kW proton and neutron beam in pion decay channel, one must solve the shielding and control beam loss in this beam line.