Concepts, Problems, & Opportunities for use of Annihilation Energy:

An Annotated Briefing on Near-Term RDT&E to Assess Feasibility

RAND Note N-2302-AF/RC

B. W. Augenstein

SOME POSSIBLE OPTIONS FOR COMPACT STORAGE (NON-EXHAUSTIVE LIST)

Storage in static or dynamic electromagnetic traps (e.g., Penning traps)
- Used in past to store antimatter
- Operational suitability limited (unless closer circumvention of space charge)
- Transportation version useful to conduct experiments
Storage in special sites in normal matter
- E.g., in liquid He bubbles
Storage of spin polarized antihydrogen
Storage of condensed state antihydrogen
- Eases space charge issues
- Stored in levitated state in cryogenic enclosures
No certain route to compact storage yet - But:
- Significantly large number of possibilities
- Need initial survey, assessment, critical experiment formulation
- Much current research relevant (e.g., Univ. of Wash.)

Compact storage suitable for storing antimatter for operational applications is an area crying out for conceptual invention. Some possible approaches are shown on the chart.

The standard electromagnetic traps are not necessarily restricted to the conventional types only.¹ Portable traps are considered in the experiment phase because, while they need "filling" at an accessible antiproton production facility, they could in principle subsequently be moved to other sites where more convenient experimentation might be possible and where more broadly based experiment teams could engage in "hands-on" work with antimatter.

The University of Washington team is specifically mentioned because of an extensive history of positron trapping and experimentation (for CPT experiments) and a carefully formulated plan to enlarge this work to antiprotons,² again for CPT related work (e.g., g-factors, inertial and gravity mass comparisons). Experiments using Penning traps range all the way from storing essentially single antiparticles for precision measurements (CPT experiments) to experiments on "maximum" filling with antiparticles (using current designs, sizes, and fields, perhaps 10¹⁰ - 10¹² particles/cc may be achievable).

Even a casual survey of the compact storage problems suggests that research spanning an enormous number of physics and engineering subfields might be usefully involved. Many trapping and storage issues can be tackled initially using normal matter, and then involve a great many disciplines of classical atomic physics. lt. should be noted that schemes other than the ones indicated, and additional variants, have been suggested for compact storage.

¹ See, for example, the collection of reprints on interesting related techniques designed for long~term storage of electrons, Reprints on Pure Electron Plasmas, Univ. of California, San Diego, Dept. of Physics, October 1984.

² See e.g., Kells Gabrielse, Helmerson, On Achieving Cold Antiprotons in a Penning Trap, IX Conf. on Atomic Physics, July 23-27, 1984, and also Kells, Remote Antiproton Sources, to appear.