Patent Number: 
Section: claims

1. A cylindrical neutron source, comprising: a cylindrical chamber; a plurality of alternatingly nested concentric or coaxial neutron generating targets and plasma ion generating regions, wherein each target is a cylinder and each plasma ion generating region is annular and has an inner and an outer plasma boundary surface; an RF antenna induction coil positioned in each plasma ion generating region; cylindrical extraction electrodes at both the inner and outer boundary surfaces of each plasma ion generating region having a voltage difference applied relative to the adjacent target, the extraction electrodes containing a plurality of longitudinal slots through which the ions are extracted from plasma ion generating regions and directed onto the targets in consequence of the applied voltage. 2. The neutron source of claim 1 wherein the plasma generating regions are deuterium ion sources. 3. The neutron source of claim 2 wherein the targets have titanium surfaces. 4. The neutron source of claim 1 wherein the source has a length of about 35 cm and a diameter of about 50 cm. 5. A cylindrical neutron source, comprising:a cylindrical chamber;at least two plasma ion generating regions and at least two neutron generating targets, a first neutron generating target disposed concentrically as a cylinder inside and spaced from a first plasma ion generating region, a second neutron generating target disposed concentrically as a cylinder outside and spaced from said first plasma ion generating region, and a second plasma ion generating region disposed concentrically outside and spaced from said second neutron generating target, all of said plasma generating regions and said neutron generating targets being disposed within said cylindrical chamber;an RF antenna induction coil disposed within each plasma generating region; anda plurality of cylindrically shaped extraction electrodes having longitudinal slots, wherein each said plasma ion generating region is annular and has an inner and an outer plasma boundary surface, each of said plasma ion generating regions having a first extraction electrode disposed adjacent said inner plasma boundary surface of said plasma ion generating regions, each of said inner plasma boundary surfaces being disposed in each of said plasma ion generating regions so as to be positioned within a portion of said plasma ion generating region that is located toward a center longitudinal axis of said neutron source, and a second extraction electrode disposed adjacent said outer plasma boundary surface of said plasma ion generating region, each of said outer plasma boundary surfaces being disposed in each of said plasma ion generating regions so as to be positioned within a portion of said plasma ion generating region that is located farther from the center longitudinal axis than is said inner plasma boundary surface, and each said first and second extraction electrodes having a voltage difference applied relative to the adjacent target. 6. The cylindrical neutron source of claim 5 wherein the plasma generating regions are deuterium ion sources. 7. The cylindrical neutron source of claim 6 wherein the targets have titanium surfaces. 8. The cylindrical neutron source of claim 5 wherein the source has a length of about 35 cm and a diameter of about 50 cm. 9. The cylindrical neutron source of claim 5 further comprising a plurality of coaxially nested alternating ion sources and targets. 10. The cylinder neutron source of claim 5, wherein each plasma generating region forms an unintermittent plasma.