DTU Risø Campus Technical University of Denmark

Primary Yields

A G-value is defined as the number of molecules available for homogeneous chemical reactions per 100 eV absorbed radiation energy.

The G-values varies with LET, temperature, dose rate and solute concentration. The survey article (A.J. Elliot, Rate Constants and G-Values for the Simulation of the Radiolysis of Light Water over the Range 0-300ºC, AECL-11073, COG-94-167) is recommended as an introduction to the subject.

A set of G-values must in itself be in mass balance and charge balance.

As an example the G-values for gamma radiation of light water, pH 7 and room temperature are:

G(OH) = 2.67
G(e-) = 2.66
G(H) = 0.55
G(H2) = 0.45
G(H2O2) = 0.72
G(H+) = 2.76
G(OH-) = 0.1
G(H2O) = -6.87

Note that e- contains one water molecule.


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