Ursell function

The Ursell function is a mathematical term associated with statistical mechanics, particularly in the context of liquids and gases. It is often used in the study of many-body systems and is related to the properties of particle interactions. In mathematical terms, the Ursell function describes correlation functions of particles in a system. Specifically, it is related to the connected parts of the n-body distribution functions, which allows researchers to factor out contributions that are due to independent particles.