Antiprotonic-hydrogen atoms

Abstract

Experimental studies of antiprotonic-hydrogen atoms have recently made great progress following the commissioning of the low-energy antiproton facility LEAR at CERN in 1983. At the same time the understanding of the atomic cascade has increased considerably through measurements of the X-ray spectra. The life history of the p-p atom is considered in some detail, from the initial capture of the antiproton when stopping in hydrogen, through the atomic cascade with the emission of X-rays, to the final antiproton annihilation and production of mesons. The experiments carried out at LEAR are described and the results compared with atomic cascade calculations and predictions of strong interaction effects.