Abstract
ABSTRACT: The potential of circulating antideuterons ( d¯ ) in the AD/ELENA facility at CERN is under active investigation. Approximately 100 d¯ per bunch could be delivered as a 100 keV beam based on measured cross-sections. These d¯ could be further decelerated to 12 keV using the GBAR scheme, enabling the synthesis of antideuterium ( D¯ ) via charge exchange with positronium, a technique successfully demonstrated with 6 keV antiprotons for antihydrogen production. The AD/ELENA facility is currently studying the possibility of increasing the d¯ rate using an optimized new target geometry. Assuming this is feasible, we propose further enhancing the anti-atom production by using laser-excited positronium in the 2P state within a cavity, which is expected to increase the D¯(2S) production cross-section by almost an order of magnitude for d¯ with 2 keV energy. We present the projected precision for measuring the antideuterium Lamb shift and extracting the antideuteron charge radius, as a function of the beam flux. GRAPHICAL ABSTRACT: D¯ production rate assuming 1e9 ortho- Ps from a flat target interact with d¯ with 12 k (blue) or inside a cavity (orange). Within the cavity, Ps can be excited to the 2P state, further increasing the charge exchange cross-section for d¯ at 2 k (green). Cross-sections are calculated using the Convergent Close Coupling (CCC, solid) method [36] and the Coulomb-Born approximation (CBA, dashed) [37].