Metastable Hydrogen Research Articles

Production of Polarized Proton Beams

A method is proposed to produce relatively intense beams of metastable hydrogen atoms and their subsequent ionization. Preliminary experiments indicate the feasibility of the proposed technique. (W.D.M.)

Hyperfine Structure of the Metastable Hydrogen Atom

The hyperfine separation $\ensuremath{\Delta}\ensuremath{\nu}(2S)$ of the metastable $2^{2}S_{\frac{1}{2}}$ state has been measured by a new atomic-beam magnetic-resonance method. Rf transitions were detected by utilizing a property peculiar to metastable hydrogen atoms, namely, that atoms with ${m}_{J}=\ensuremath{-}\frac{1}{2}$ decay much more rapidly in passing through a magnetic field of about 575 gauss than do atoms with ${m}_{J}=+\frac{1}{2}$. We found that $\ensuremath{\Delta}\ensuremath{\nu}(2S)=177556.86\ifmmode\pm\else\textpm\fi{}0.05$ kc/sec. From this result and the very accurately known hyperfine separation $\ensuremath{\Delta}\ensuremath{\nu}(1S)$ of the ground state, we obtain $R\ensuremath{\equiv}\frac{\ensuremath{\Delta}\ensuremath{\nu}(2S)}{\ensuremath{\Delta}\ensuremath{\nu}(1S)}=\frac{1}{8}(1.0000346\ifmmode\pm\else\textpm\fi{}0.0000003)$. The deviation of $R$ from the presently available theoretical value suggests the existence of a higher-order quantum-electrodynamic term.A method of velocity selection by electron impact is described.

Fine Structure of the Hydrogen Atom. Part II

In the first paper of this series, the shift of the $2^{2}S_{\frac{1}{2}}$ level of hydrogen was determined to be 1000 Mc/sec. A new apparatus differing from the original one in details, but not in principle, has been built in order to improve the accuracy of the above result. This provides a greater yield of metastable hydrogen atoms, a more homogeneous magnetic field, and more accurate means of measurement of magnetic field and frequency. With these improvements, preliminary measurements of considerably increased accuracy have been made on both hydrogen and deuterium. The transitions observed were $2^{2}S_{\frac{1}{2}}$, $m=\frac{1}{2}$, to $2^{2}S_{\frac{1}{2}}$, $m=\ensuremath{-}\frac{1}{2}$, as well as to $2^{2}P_{\frac{1}{2}}$, $m=\frac{1}{2}$ and $m=\ensuremath{-}\frac{1}{2}$. The first transition permits observation of the hyperfine structure of $2^{2}S_{\frac{1}{2}}$, as well as an accurate calibration of magnetic field. Hyperfine structure was also resolved for the last transition in hydrogen. There was no observable difference between the level shifts for hydrogen and deuterium which may be taken as 1062\ifmmode\pm\else\textpm\fi{}5 Mc/sec. Later papers of this series will deal with the numerous experimental and theoretical corrections necessary to obtain a level shift accurate to 1 Mc/sec.