Term in dosimetry of ionizing rays; energy transfer of an ionizing particle to the matter penetrated by radiation. The linear energy transfer is equal to the energy dE which a charged particle loses at a distance dl.

The linear energy transfer is indicated in keV/µm. The following relation has been fixed between the quality factor Q (L) and the unlimited linear energy transfer L:

 

Unlimited linear energy transfer L in water, (keV µm-1)

Q(L)

<10

1

10 – 100

0.32 L – 2.2

>100

300 / L

 

Relation between the linear energy transfer and the quality factor