Lasing has been achieved in many different media using a wide variety of excitation mechanisms including low-energy electron or proton beams and recoiling fission products. In all cases, the power density produced in the medium has been the critical parameter. Recent calculations indicate that a region of high-power density can be achieved in high-density lasing media by allowing antiprotons to annihilate in the material with an intense magnetic field present. Because of the long range of energetic annihilation products, the media can be gaseous, liquid, or solid. The thermalization time is the critical parameter for this excitation mechanism which for liquid-density media, such as Ar-Xe mixtures, is about 2.1 ns. Based on these calculations power density of about 100 MW/cm/sup 2/ can be achieved using a level of antiprotons that is currently available today. Development of an antiproton pumping source may allow fundamental reaction kinetics in a wide variety of lasing systems to be performed in a university environment. The results of the calculations in a liquid medium and at different magnetic field strength will be presented. In addition, the design of an ongoing experiment using an 800 MeV proton beam to pump a liquid density excimer cavity will be discussed. These preliminary experiments intend to focus on fundamental kinetics and on the effects of a strong magnetic field on reactions. 13 refs., 7 figs
