A variety of static local field distributions and their associated static ZF
Kubo-Toyabe
µSR relaxation functions are derived by mathematical
manipulation, often without reference to any particular physical model of
any particular real material. The relation of such distributions and
relaxation functions, not already in use, to
µSR in the lab is not
clear. However, the static Lorentzian Kubo-Toyabe function, which is in use,
is well known to be pathological because the field distribution has infinite
second moment, which causes the relaxation function to have a slope as
.
Most of the distributions discussed do not have such a
pathology.