"Linear Energy Transfer" (LET) is the linear density of energy lost by a charged ionizing particle travelling through matter.Typically, this measure is used to quantify the effects of ionizing radiation on biological specimens or electronic devices.
Applicable units are those of quantitykind:LinearEnergyTransfer
http://en.wikipedia.org/wiki/Linear_energy_transfer
http://dbpedia.org/resource/Linear_energy_transfer
"Linear Energy Transfer" (LET) is the linear density of energy lost by a charged ionizing particle travelling through matter.Typically, this measure is used to quantify the effects of ionizing radiation on biological specimens or electronic devices.
For ionizing charged particles, $L_\Delta = \frac{dE_\Delta}{dl}$, where $dE_\Delta$ is the mean energy lost in elctronic collisions locally to matter along a small path through the matter, minus the sum of the kinetic energies of all the electrons released with kinetic energies in excess of $\Delta$, and $dl$ is the length of that path.
http://www.iso.org/iso/catalogue_detail?csnumber=31895