Photo-Equilibrium of Barium

G. T. Best, Victor L. Corbin, Air Force Cambridge Research Laboratories (U.S.)

Published Nov 30, 1971• 1 citation

Abstract

A model for numerical simulation of the solar pumping of a simple atomic system is constructed and compared with the exact analytical solution. The process is then extended to cover the more complex 5-level 5-transition barium ion term scheme and the 61-level 86-transition barium neutral term scheme. An advantage of the step-wise simulation is that in addition to yielding the equilibrium relative level populations and transition intensities, it also permits the dynamic grow-in to equilibrium to be studied. The neutral barium system has also been studied with the inclusion of photoionization from each of several metastable levels.

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Photo-Equilibrium of Barium

G. T. Best, Victor L. Corbin, Air Force Cambridge Research Laboratories (U.S.)

Published Nov 30, 1971• 1 citation

OpenAlex

Abstract

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6s6p\phantom{\rule{0.2em}{0ex}}^{3}P_{1}

state. Additionally, we report a particularly simple and efficient trap loading technique that employs an inexpensive uv epoxy curing lamp to generate photoelectrons.

We demonstrate an experimental technique that selects the nuclear spin I=0 isotope

^{138}\mathrm{Ba}

for spectroscopic measurements from a beam of natural barium containing seven stable isotopes. A cw dye laser is used to optically pump the I=3/2 isotopes

^{135}\mathrm{Ba}

and

^{137}\mathrm{Ba}

into the metastable 6s5d

^{1}

{\mathit{D}}_{2}

and

^{3}

{\mathit{D}}_{1,2}

levels via the 6s6p

^{1}

{\mathit{P}}_{1}

excited state, leaving nearly pure

^{138}\mathrm{Ba}

in the ground state. Photoionization spectra of the excited 5d6p

^{3}

{\mathit{D}}_{1}

even isotope state recorded with optical pumping of

^{135}\mathrm{Ba}

and

^{137}\mathrm{Ba}

to the metastable levels are essentially devoid of forbidden features associated with the hyperfine interaction in the odd isotopes.