A neutron detector technology based on 10B thin film conversion of
neutrons
and detection of neutron capture reaction products in a counter gas within a thin
straw tube detector body is described. This neutron detector is based on gas-filled
thin wall straw tubes, modified for the conversion of neutrons in a very thin coating,
or layer, of 10B, applied for example as a sputter-coated film of 10B4C,
that lines the interior, or inside of the straw tube surface; and the subsequent
detection of the neutron reaction products in the counter gas. One embodiment of
this invention employs a closely-packed array of 10B4C-lined
straw tubes employing a very thin and therefore high efficiency 10B4C
layer, hence removing the barrier to efficient neutron capture reaction product
escape while still providing for efficient neutron capture by providing a plurality
of very thin 10B converters, each individual converter element providing
efficient reaction product escape. Using such densely packed straw tube detectors
of small diameter, a reasonable stack depth allows a high neutron detection efficiency
to be achieved on the 1-10 wavelength range of thermal neutrons.
The position of each interacting neutron can be accurately obtained with for example,
resistive charge division readout combined with straw decoding electronics to determine
the identity of the struck straw.
