Patent Number: 
Section: claims

1. A target grid assembly for employment in a target assembly used to produce radioisotopes by bombarding a target material contained in the target assembly with a particle beam, the target assembly further including a target body defining a target reservoir for receiving the target material and a target window for sealing the target reservoir, said target grid assembly comprising: a vacuum window;  a target grid defining a target grid portion, a helium input and a helium output, said target grid portion defining a plurality of target grid supports which are configured to form a plurality of target grid oblong openings, said target grid portion defining an upstream side and a downstream side, said vacuum window being positioned against said upstream side, the target window being supported between said downstream side and the target body, a helium space being defined by said plurality of target grid oblong openings between said vacuum window and the target window and being configured such that helium is injectable into said helium space via said helium input and extractable from said helium space via said helium output; and  an interception grid positioned upstream of said vacuum window, said interception grid defining an interception grid portion which defines a plurality of interception grid supports, said interception grid supports being configured to form a plurality of interception grid oblong openings, said vacuum window being positioned between said interception grid supports and said target grid supports. 2. The target grid assembly of  claim 1  further including a slotted O-ring defining a first slot and a second slot, said first slot being spaced apart from said second slot such that said first slot coincides with said helium input and said second slot coincides with said helium output, said first slot extending perpendicular to an upper portion of each of said plurality of target grid oblong openings and said second slot extending perpendicular to a lower portion of each of said plurality of target grid oblong openings such that helium injected into said helium input flows into said upper portion of each of said plurality of target grid oblong openings thereby filling said helium space and flows out of said lower portion of each of said plurality of target grid oblong openings into said second slot and through said helium output thereby establishing a helium cooling regime. claim 1 3. The target grid assembly of  claim 1  wherein said interception grid supports and said target grid supports are aligned. claim 1 4. A target grid assembly for employment in a target assembly used to produce radioisotopes by bombarding a target material contained in the target assembly with a particle beam, the target assembly further including a target body defining a target reservoir for receiving the target material and a target window for sealing the target reservoir, said target grid assembly comprising: a vacuum window; and,  a target grid defining a target grid portion, a helium input and a helium output, said target grid portion defining a plurality of target grid supports which are configured to form a plurality of target grid oblong openings, said target grid portion defining an upstream side and a downstream side, said vacuum window being positioned against said upstream side and the target window being supported between said downstream side and the target body, a helium space being defined by said plurality of target grid oblong openings between said vacuum window and the target window;  a slotted O-ring defining a first slot and a second slot, said first slot being spaced apart from said second slot such that said first slot coincides with said helium input and said second slot coincides with said helium output, said first slot extending perpendicular to an upper portion of each of said plurality of target grid oblong openings and said second slot extending perpendicular to a lower portion of each of said plurality of target grid oblong openings such that helium injected into said helium input flows into said upper portion of each of said plurality of target grid oblong openings thereby filling said helium space and flows out of said lower portion of each of said plurality of target grid oblong openings into said second slot and through said helium output thereby establishing a helium cooling regime; and,  an interception grid positioned upstream of said vacuum window, said interception grid defining an interception grid portion which defines a plurality of interception grid supports, said interception grid supports being configured to form a plurality of interception grid oblong openings, said vacuum window being positioned between said interception grid supports and said target grid supports, said interception grid supports and said target grid supports being aligned.