Accelerator Possibilities for Low Energy Antiprotons at the Fermi National

There is considerable interest in the deceleration of antiprotons for particle physics, atomic physics, gravitational experiments, PET radioisotope production, antiproton capture therapy, and deep-space spacecraft propellant. The only facility in the world presently capable of producing large uxes of usable antiprotons is the Fermi National Accelerator Laboratory (FNAL). Unfortunately, at this time FNAL has no beamline for extracting decelerated antiprotons to experiments or to portable Penning traps for commercial distribution. In this paper a vision is developed for decelerating antiprotons to progressively lower energies and higher eÆciencies. 1 PET Radioisotope Production The typical positron-emitting isotopes used or desired for medical applications are C, N, O, and F. Their half-lives are respectively 20, 10, 2, and 110 minutes. In order to create these isotopes and inject them into the patient before the positron emission is depleted, it has been necessary to have a nearby accelerator for radioisotope generation. In the U.S. there are over 1700 institutions that have PET imaging capabilities, but only 40 isotope-generation clinics exist. Even though the number of disorders being diagnosed by PET is increasing rapidly, the primary obstacle to PET applications is the lack of isotope availability. The problem is that the high cost of cyclotrons restricts the number of PET centers. This availability problem can potentially be eliminated by a commercial distribution system for antiprotons. Imagine a compact, portable Penning trap which would be brought to any hospital with a PET imaging capability on a regular basis (like deliveries of liquid nitrogen). By spilling antiprotons from the trap into the sample at a kinetic energy of approximately 1 MeV, PET isotopes can be produced in a small, portable, shielded enclosure. It would be possible literally to produce the radioisotopes at the patient's bedside. This makes isotopes such as O, which holds so much promise for the diagnosis of brain tumors, viable for use in a hospital environment.