Abstract: Microsized devices operable to emit neutrons in a selective manner are provided. The devices are configured so that the rate of neutron emission can be varied, either actively or passively. The devices comprise an a-particle emitting material and a neutron producing target material that when aligned and/or positioned a predetermined distance apart emit neutrons. The rate of neutron emission can be slowed or stopped by taking the materials out of alignment and/or attenuating the ?-particles being directed toward the neutron producing target material.

Abstract: An isotropic neutron detector includes a spherical secondary particle radiator component and a plurality of stacked semiconductor detectors, A first semiconductor detector is coupled to at least a portion of the spherical secondary particle radiator component, forming a portion of a first concentric shell thereover. A second semiconductor detector coupled to at least a portion of the first semiconductor detector, forming a portion of a second concentric shell thereover.

Abstract: Microsized devices operable to emit neutrons in a selective manner are provided. The devices are configured so that the rate of neutron emission can be varied, either actively or passively. The devices comprise an a-particle emitting material and a neutron producing target material that when aligned and/or positioned a predetermined distance apart emit neutrons. The rate of neutron emission can be slowed or stopped by taking the materials out of alignment and/or attenuating the ?-particles being directed toward the neutron producing target material.