High-OrbitalS-State Capture ofπ−Mesons by Protons

Abstract

The consequences of the very short capture time for ${\pi }^{-}$ mesons in liquid hydrogen, recently measured by Fields, Yodh, Derrick, and Fetkovich, are discussed. It is pointed out that collisional de-excitation mechanisms, even including the Stark effect enhancement of capture, seem inadequate to explain the experiment. Alternative possibilities are discussed.