Antiproton and Electron Plasma Behavior and its Control for Production of Ultraslow Antiproton Beams

For the production of ultraslow antiproton beams, decelerated antiprotons were captured in an electro‐magnetic trap and cooled by collisions with preloaded electrons. This electron cooling feature was non‐destructively monitored by measurement of electrostatic oscillations of the electron plasma. The radial distribution of the plasma was controlled for efficient cooling and extraction by utilizing rotating wall field technique.