Understanding Neutron Radiography Post Exam Reading VIII-Part 2a of 2A

Ionization tracts. When particulate or electromagnetic energy penetrates a
cell, one or more ionizations will likely take place. While the precise site of
interaction is somewhat random, ionizations will distribute along distinct paths.
The density of ionizations along a given path relates inversely to kinetic
energy of the particle or photon.
Thus a decelerating particle produces the greatest number of ionizations just
before coming to rest. Comparing particles or photons, it follows also that LET
for a gamma ray may be smaller than LET for an x-ray.
Charlie Chong/ Fion Zhang
https://www.med-ed.virginia.edu/courses/rad/radbiol/01physics/phys-03-03.html