Positronium Rydberg Excitation Diagnostic In A 1t Cryogenic Environment

Forming a pulsed beam of cold antihydrogen using charge-exchange with Rydberg positronium (Ps) is the goal of the AEgIS collaboration, which aims to a first gravity measurement on neutral antimatter. Recently achieved results in Ps formation and laser spectroscopy in the main AEgIS apparatus are summarized. First, Ps has been produced using nanochanneled silicon targets in a cryogenic environment (similar to 15 K) with 1 T magnetic field and observed by means of Single-Shot Positron Annihilation Lifetime Spectroscopy. The first demonstration of Ps n=3 excitation has been obtained as well using the same technique, validating the proof-of-concept of AEgIS. Subsequently, a new fast and high sensitivity detection method for laser-excited Ps in high magnetic field has been developed, using the combination of laser/field ionization and an high sensitivity MCP detector coupled to a low noise CMOS camera. This technique will form the basis of future experiments involving Rydberg Ps spectroscopy in AEgIS.