Observation of Long-Lived Muonic Hydrogen in the 2S State
Atomic Physics
2009-11-13 v1
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.
Cite
@article{arxiv.physics/0610100,
title = {Observation of Long-Lived Muonic Hydrogen in the 2S State},
author = {Randolf Pohl and Herbert Daniel and F. Joachim Hartmann and Peter Hauser and Franz Kottmann and Valery E. Markushin and Markus Mühlbauer and Claude Petitjean and Wolfgang Schott and David Taqqu and Peter Wojciechowski-Grosshauser},
journal= {arXiv preprint arXiv:physics/0610100},
year = {2009}
}
Comments
4 pages, 2 figures, accepted for publication in Physical Review Letters