A time-of-flight, atomic-beam magnetic-resonance method was used to compare the
gJ factor of
2p33s5S2 atomic oxygen with the
gJ factor of metastable
23S1 atomic helium in magnetic fields of 3209 and 4228 G. The metastable oxygen and helium atoms were produced in a pulsed radio-frequency discharge source and after traversing the apparatus were detected by electron emission from a tungsten surface. By collecting data only in a given interval of the time-of-flight distribution the
O(5S) and
He(3S) states were isolated from other discharge products. From 158 pairs of resonances taken with four relative field and hairpin orientations the atomic magnetic
g factor is ${g}_{J}(^{5}S_{2}, ^{16}\mathrm{O})=\frac{{\ensuremath{\mu}}_{J}}{J}=\ensuremath{-}2.0020910(10)$.
The lowest Rb metastable autoionizing level has been identified by a rf resonance measurement of the g factors of the various hyperfine sublevels. Of the two lowest-lying metastable state assignments,
4p5(2P)5s5p(3P)4D27 and
4p54d(3F)5s4F29, only components of the
4D27 were observed in the metastable beam. The atomic-beam resonance method employed resembles traditional methods except that it exploits the differential metastability of the fine-structure levels instead of magnetic deflection for state selection.
The four metastable states of atomic barium comprising the
6s5d configuration have been studied by atomic-beam magnetic resonance, and information concerning their
g factors has been obtained. Data from this work agree with that obtained recently by v. Oppen using a different method, and agreement is also obtained with theory.