Observation of Long-Lived Muonic Hydrogen in the 2S State

Abstract

The kinetic energy distribution of ground state muonic hydrogen atoms mu-p(1S) is determined from time-of-flight spectra measured at 4, 16, and 64 hPa H2 room-temperature gas. A 0.9 keV-component is discovered and attributed to radiationless deexcitation of long-lived mu-p(2S) atoms in collisions with H2 molecules. The analysis reveals a relative population of about 1%, and a pressure-dependent lifetime (e.g. (30.4 +21.4 -9.7) ns at 64 hPa) of the long-lived mu-p(2S) population, equivalent to a 2S-quench rate in mu-p(2S) + H2 collisions of (4.4 +2.1 -1.8) 10^11 s^-1 at liquid hydrogen density.

4 pages, 2 figures, accepted for publication in Physical Review Letters

References in corpus (4)

• Theory of Light Hydrogenlike Atoms
• Proton structure effects in muonic hydrogen
• Lamb Shift in Muonic Hydrogen
• Collisional deexcitation of exotic hydrogen atoms in highly excited states. II. Cascade calculations

Cited by in corpus (17)

• Muonic hydrogen and the proton radius puzzle
• Pionic deuterium
• Lamb Shift in Muonic Hydrogen. II. Analysis of the Discrepancy of Theory and Experiment
• The next generation of laser spectroscopy experiments using light muonic atoms
• Why three-body physics do not solve the proton radius puzzle
• Muonic hydrogen cascade time and lifetime of the short-lived $2S$ state
• Theoretical and computational study of the energy dependence of the muon transfer rate from hydrogen to higher-Z gases
• Line shape of the muH(3p - 1s) hyperfine transitions
• Lifetime and population of the 2S state in muonic protium and deuterium
• Multipass laser cavity for efficient transverse illumination of an elongated volume
• The isotopic effects in the scattering and the kinetics of the atomic cascade
• Line shape analysis of the K$\beta$ transition in muonic hydrogen
• Collision-induced radiative quenching and other disintegration modes of the $2S$ state of muonic hydrogen and deuterium atoms
• Radiative decay of muonic molecules in resonance states
• Differential cross sections for muonic atom scattering in solid hydrogenic targets
• Analytical matrix elements of the Uehling potential in three-body systems, and applications to exotic molecules
• Energy interval 3S-1S in muonic hydrogen