=
108
Sey,
This instrument however, has its
pulses produced by the neutron of a reaction
with boron in the filling and as a result,
it's responses is essentially flat down to
neutron energies of about 10 KEV.
Now, the biacing circuit is de-
signed then, to accept pulses which are
greater than the minimum to discriminate be-
tween ambient nolee and radiation of other types.
There's another way in which you
can fail to diccriminate between neutron
radiation and radiation - well, specifically
ganma radiation and this is in the case known
as gamma "pylo®,
This 19° desipned on the asecumption
that the incoming pulses can be meoognized
ag individual events.
This ia the bias level.
Now, ordi-
narily, if they come in, the neutron pulse
might look like that roughly -- if the instantaneous dose rate is sufficiently large, they
are no longer resolved into individual events
and the gamma rate; pulse height then, is the
sum of the individual pulse heights produced
and as a result, may override the bias and be
counted as a neutron pulce,