中国极化电子离子对撞机探测器设计

核子是构成宇宙可见物质的最主要成分，也是研究强相互作用的最佳实验室。对核子内部结构的研究是当前理论和实验研究的重要前沿。在核子内部结构的实验研究中，电子- 离子对撞机(Electron Ion Collider, EIC)是最理想的装置，能提供核子内部最清晰的图像，是人类认识物质世界深层次结构，特别是核子与原子核结构最理想的工具。中国极化电子离子对撞机EicC项目，设想在已开建的HIAF 高能离子束的基础上进行升级:将离子束流升级成15~20 GeV 的极化束流，建设3~5 GeV 高能极化电子束流，实现质心系能量为10~20 GeV双极化电子- 离子对撞，在海夸克能区对核子内部结构进行精细测量，并对质子质量、奇特强子态等诸多重要物理课题展开研究。在本文中，我们开发了EicC 快模拟软件，对探测器性能进行参数化模拟；通过物理模拟汇集EicC探测需求，利用探测器模拟软件进行优化并提出EicC 探测器谱仪的初步设计方案。该谱仪方案提供了接近全立体角的覆盖范围和大动量范围内的粒子鉴别能力，兼顾EicC项目丰富的物理课题。

Detector Design of the Polarized Electron Ion Collider in China

Nucleon, the main building block to the visible matter in the universe, is an ideal laboratory to study the strong interaction. In the experimental study of nucleon structure, Electron Ion Collider(EIC) plays important role. EIC is a super electron-microscope being able to take clear image of the inner structure of the nucleon, and hence is an effective tool to gain insights into the fundamental constituents of matter, e.g., especially the structures of the nucleon and nuclei. The Electron-ion collider in China(EicC) project is proposed based on the HIAF facility by promoting its ion beam to an energy around 15~25 GeV, which is then enforced to collide with an electron beam of 3~5 GeV. Both beams are polarized and their center-of-mass energy is 10~20 GeV. The main physics motivations include the precision measurements to the nucleon internal structure in the sea-quark region, and the promotion of our understanding of the origin of proton spin and mass, the study of exotic states, etc. In the paper, a fast simulation package based on parametrisation is developed for EicC. With the simulation package, one EicC detector conceptual design is proposed based on the virous physics simulations.