APS refers to american physical society, which is the largest physical organization in the world. LS refers to an important member service project launched by the organization-the "Express Status" (referred to as "LS") in the database of Physical Review Express. This term can be simply translated as "paper status" in Chinese, and is usually used to indicate the current review progress and problems that need to be reviewed when an editor reviews a paper.

LS can be divided into two types, one is LS-A, which means "approved" status; The other is LS-B, which means "Unapproved" status. Different kinds have different meanings. If a paper is in LS-A status, it means that it has been carefully reviewed and evaluated by the editor and passed all the review steps. If a paper is in LS-B state, it shows that there are still problems to be solved in the process of reviewing the paper.

It is worth mentioning that the LS system of APS is not available in all physical journals. This service is only available in Physical Review Express, which is one of the two major journals of the organization. Because of its popularity and importance, more and more physicists began to use LS system to track the progress and comments of their papers. The system provides efficient, transparent and standardized services for physical research and promotes the cooperation and development of academic research.