A Multicell Trap for Positron Storage

There are many potential applications of high-capacity and/or portable antimatter traps, including multiplexing the output of high-flux positron beams, study of electron-positron plasmas, and eventually the construction of an annihilation gamma-ray laser at 0.51 MeV. We describe recent progress in the design and construction of a novel multicell Penning-Malmberg (PM) trap to store in excess of $5 \times 10^{11}$ positrons.\footnote{J. R. Danielson, T. R. Weber, and C. M. Surko, {\it Phys. Plasmas} {\bf 13}, 123502 (2006).} The construction and planned objectives of a test electrode structure will be discussed. A key issue to be determined is the quality of confinement in off-axis cells in the less uniform portions of the magnetic field near the ends of the magnet. Protocols for filling off-axis cells and handling plasmas with kiloelectron volt levels of space charge will be described. A new scenario to rapidly dump the contents of the multicell trap will be discussed.