effective LET (for particle radiation)

The linear energy transfer (LET) modified to account for the change in total energy transferred from an incident ion as it traverses a sensitive volume when the path of the ion is not normal to the surface of that volume.

NOTE 1 The cosine dependence may be applicable for this modification. Caution must be utilized; see annex B of JESD57.

LET(θ ) = LET(0°) / cos θ

where θ is the angle of incidence of the ion (i.e., the angle between the ion path and the normal at the point of incidence).

NOTE 2 Many modern devices do not follow the above equation, so the experimenter may have to determine the LET(θ ) from the geometry of a particular device.

NOTE 3 The equation in note 1 is valid only when the depth of the sensitive volume is less than the other two dimensions in the RPP model.

References