Mass Production of Antimatter for High-Energy Propulsion

Abstract

Theoretical and experimental work completed during the past decade indicates that interstellar propulsion systems based on the annihilation of antiprotons in a propellant will be feasible during the next several decades. The major technical dife culty appears to be the efe cient production of antimatter. Estimates based on the use of currently available technologies indicate that the equipment required to produce and store antimatter would be inefe cient and expensive. Hence, potentially more efe cient processes should be examined. Currently, antiprotons are produced by colliding high-energy protons with stationary heavy-element targets, such as tungsten. Other approaches, for which experimental data are available, indicate that there are production methods that are more efe cient. Several of these have been examined, and some show a signie cant improvement in efe ciency, but they may be dife cult to implement. Two methods examined will be discussed along with some technical advantages and disadvantages. In the e rst method, antiprotons and pions are collected from the collision of high-energy protons and a heavy-element target. Many more pions are produced than antiprotons. The pions are then directed toward the same target or a different target. The collision of pions and heavy nuclei have a higher probability for the production of antiprotons and would signie cantly increase the number of antiprotons produced. In the second method,a recirculatingelectron/positroncolliderwouldproducemultiplecollisionsneara resonanceforproducing antiprotons by using beam wigglers as in free-electron lasers. This technique would allow a signie cant increase in the number of interactions that would occur and would proportionally increase the antiproton production.