Dr Lots-o'watts said:You might want to provide a reference or at least a definition for "hard sphere".
In the classical sense, it is surely unlikely that three bodies make contact simultaneously. But are you talking of a classical or a quantum system?
Collision cross section is a measure of the effective size of a molecule or particle in a gas. It is used to quantify the likelihood of a collision between two particles in a gas phase system.
A 3-body system refers to a system of three particles or bodies that interact with each other through forces, such as gravity or electrostatic forces. This type of system is commonly found in physics and astronomy, and can be described using mathematical models.
One common misconception is that larger particles will always have a larger collision cross section. In reality, the shape and orientation of the particles can also affect the collision cross section. Additionally, the presence of a third particle in a 3-body system can also alter the collision cross section.
Understanding collision cross section is important in fields such as atmospheric science, chemistry, and physics. It helps scientists predict the behavior of particles in a gas phase system, and can also aid in the development of new technologies and processes.
Collision cross section for 3-body systems is often explored through computer simulations and mathematical models. These methods allow scientists to study the effects of various factors, such as particle size and shape, on the collision cross section. Experimental techniques, such as mass spectrometry, can also be used to measure collision cross section in a laboratory setting.