Search for long-lived 2S muonic hydrogen in H2 gas

P. O. Egan, S. Dhawan, V. W. Hughes, D. C. Lu, F. G. Mariam, P. A. Souder, J. Vetter, G. Zu Putlitz, P. A. Thompson, A. B. Denison

Research output: Contribution to journalArticlepeer-review

30 Scopus citations


We have searched for long-lived 2S muonic hydrogen (-p) in H2 gas at 0.8 atm. The state could be detected by observing delayed 1.9-keV 2P1S photons from collisionally quenched -p(2S). The observed upper limit (90% confidence level) for the fraction,f2S, of -p(2S) with lifetime 2S in the gas in the range, 100<2S<1000 ns, is f2S<2%. Our results are consistent with the view that most of the -p(2S) have kinetic energies greater than the 0.3-eV threshold for the inelastic collision -p(2S)+H2-p(2P)+H2 and hence are rapidly quenched. We have also measured the relative Lyman line intensities in muonic hydrogen and muonic helium at 0.8 atm with solid-state detectors [Ge for -He4 and Si(Li) for -p]. The results are (KKtotal)-p=0.460.06, KKtotal)-He4=0.760.04, (KKtotal)-He4=0.040.02. These results imply that about 7.5% of -p atoms cascade to the 2S state.

Original languageEnglish (US)
Pages (from-to)1152-1163
Number of pages12
JournalPhysical Review A
Issue number3
StatePublished - 1981
Externally publishedYes

ASJC Scopus subject areas

  • Atomic and Molecular Physics, and Optics


Dive into the research topics of 'Search for long-lived 2S muonic hydrogen in H2 gas'. Together they form a unique fingerprint.

Cite this