Available energy (particle collision)

For a discussion about the meaning of the term in classical thermodynamics, see Exergy.

In particle physics, the available energy is the energy in a particle collision available to produce new matter from the kinetic energy of the colliding particles. Since the conservation of momentum must be held, a system of two particles with a net momentum may not convert all their kinetic energy into mass - and thus the available energy is always less than or equal to the kinetic energy of the colliding particles. The available energy for a system of one stationary particle and one moving particle is defined as:

$E_a = \sqrt{2 m_t c^2 E_m + (m_t c^2)^2 + (m_k c^2)^2}$

where

m_t is the mass of the stationary target particle,

m_k is the mass of the moving particle,

E_m is the kinetic energy of the moving particle, and

c is the speed of light.

See also

• Threshold energy
• Matter creation