Quantity for ionising uncharged particles, defined by the quotient of [math]dE_{tr}[/math] by [math]dm[/math], where [math]dE_{tr}[/math] is the mean sum of the initial kinetic energies of all the charged particles liberated in a mass [math]dm[/math] of a material by the uncharged particles incident on [math]dm[/math], thus:
[math] K = \frac{dE_{tr}}{dm} [/math]
The SI unit of kerma is joule per kilogram (J kg-1), and its special name is gray (Gy).
‘Kerma’ is an acronym for ‘kinetic energy released in a mass’.
ICRP Publication 116, 2010
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from ICRP Publication 103, 2007; ICRP Publication 119, 2012; ICRP Publication 120, 2012; ICRP Publication 135, 2017; and ICRP Publication 136, 2011
The quotient of the sum of the kinetic energies, [math]dE_{tr}[/math], of all charged particles liberated by uncharged particles in a mass [math]dm[/math] of material, and the mass [math]dm[/math] of that material.
[math] K = \frac{dE_{tr}}{dm} [/math]
Kerma is defined as a non-stochastic quantity and [math]dE_{tr}[/math] is the expectation value of the sum of the kinetic energies. The unit for kerma is joule per kilogram (J kg-1) and its special name is gray (Gy).