Thermalisation

In physics, thermalisation (in American English "thermalization") is the process of particles reaching thermal equilibrium through mutual interaction.

When a molecule absorbs energy, as in the technique of molecular fluorescence, the lifetime of the excited state is ~10^-12 sec. Then it rapidly loses energy to the lowest level of the lowest excited state; this is called thermalization.

In general the natural tendency of a system towards a state of equipartition of energy or uniform temperature.This raises the system’s entropy.

Examples of thermalisation include:
* the achievement of equilibrium in a plasma
* the process undergone by high-energy neutrons as they lose energy by collision.

External links

* [http://sdphca.ucsd.edu/coll_therm.html Collisions and thermalization]
* [http://www.nrc.gov/reading-rm/basic-ref/glossary/thermalization.html U.S. Nuclear Regulatory Commission Glossary]