电荷宇称对称性破缺（CP破坏）是解释宇宙正反物质不平衡的必要条件。理解CP破坏的根源和动力学机制是物理学的关键问题之一。现有实验发现了K和B介子系统的CP破坏，但重子领域的CP破坏亟待证实。标准模型的CKM夸克混合机制提供了CP破坏的一个来源，但提供的CP破坏远不足以解释正反物质不对称问题。研究重子衰变是寻找CP破坏新来源的重要方式。大型强子对撞机上的LHCb实验提供大量的重子衰变数据，为开展深入的重子CP破坏研究提供了良好机会。本项目基于2015-2017年期间的LHCb实验数据，开展两方面的探索：研究含底夸克重子的衰变，寻找标准模型所预言的重子CP破坏；研究含粲夸克重子和含奇异夸克重子的衰变，检验标准模型和寻找CKM以外的CP破坏新来源。这将是LHCb上对重子CP破坏的首次系统研究。预期能把主要重子CP破坏的测量精度比现有实验显著提高。

CP violation is a necessary condition to explain the matter-antimatter imbalance of the Universe. Understanding its origin and dynamics is a key problem in physics. CP violation has been discovered in the K and B systems, but not yet in the baryon sector. CKM mechanism is the only origin of CP violation in the Standard Model, but the CP violation from this origin is insufficient to explain the observed matter-antimatter imbalance. Study of baryon decays is an important way to look of new origin of CP violation beyond CKM. The LHCb experiment at the Large Hadron Collider collects a big amount of data of baryon decays, providing a great opportunity to study CP violation in baryon decays. This program will be based on the LHCb data collected during 2015-2017 and includes two parts: study of b-baryon decays to look for CP violation in decays that are expected to have sizable CP violation effect in the Standard Model; study of c-baryon and hyperon decays to test the Standard Model and look for new sources of CP violation. This will be the first systematic study of CP violation in baryon decays at LHCb, and will significantly improve precision of the major measurements compared with the previous studies of CP violation in the baryon sector.