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Title: Collisional processes involving the metastable 6s5d [sup 3]D[sub J] levels of barium

Abstract

The authors have studied a number of collisional processes involving the metastable 6s5d [sup 3]D[sub J] levels of barium. The metastable levels were populated through optical pumping of the 6s[sup 2] [sup 1]S[sub 0] [yields] 6s6p [sup 3]P[sup 0][sub 1] intercombination transition at 791.13 nm, followed by either spontaneous or stimulated decay into the [sup 3]D[sub 1,2] levels. Collisional mixing further redistributed population over the three [sup 3]D[sub J] levels. The authors measured line shapes and foreign-gas broadening rates for the 6s5d [sup 3]D[sub 1] [yields] 5d6p [sup 1]D[sup 0][sub 2], 6s5d [sup 3]D[sub 2] [yields] 5d6p [sup 3]F[sub 3], and 6s5d [sup 3]D[sub 3] [yields] 5d6p [sup 3]F[sub 4] transitions by using a cw pump laser to populate the metastable levels and monitoring the absorption of a weak cw probe laser. In additions, line shapes and broadening rates were also measured for the 6s[sup 2] [sup 1]S[sub 0] [yields] 6s6p [sup 1]P[sup 0][sub 1] resonance and 6s[sup 2] [sup 1]S[sub 0] [yields] 6s6p [sup 3]P[sup 0][sub 1] intercombination transitions. Using the broadening rate coefficients determined for these transitions, they were able to accurately estimate the total number density of barium atoms in the heat-pipe oven, as well as themore » number density of atoms in the metastable levels when optically pumping the vapor. The authors estimate that 60% of the barium atoms were pumped into the metastable levels using 200 mW of cw laser power. They have also developed a useful technique for studying time-resolved line shapes that combines the time resolution capabilities of a pulsed laser with the frequency resolution of a narrowband, single-mode cw laser. With this technique, they have measured time-dependent line shapes for transitions involving metastable levels using a pulsed pump laser and a cw probe. A comparison of the pulsed and cw line shapes indicates that experimental conditions are below the threshold where Stark broadening is significant.« less

Authors:
Publication Date:
Research Org.:
Lehigh Univ., Bethlehem, PA (United States)
OSTI Identifier:
7003901
Resource Type:
Miscellaneous
Resource Relation:
Other Information: Thesis (Ph.D.)
Country of Publication:
United States
Language:
English
Subject:
74 ATOMIC AND MOLECULAR PHYSICS; BARIUM; COLLISIONS; METASTABLE STATES; ARGON; ATOM-ATOM COLLISIONS; ATOM-MOLECULE COLLISIONS; ENERGY-LEVEL TRANSITIONS; NITROGEN; ALKALINE EARTH METALS; ATOM COLLISIONS; ELEMENTS; ENERGY LEVELS; EXCITED STATES; FLUIDS; GASES; METALS; MOLECULE COLLISIONS; NONMETALS; RARE GASES; 664300* - Atomic & Molecular Physics- Collision Phenomena- (1992-)

Citation Formats

Ehrlacher, E A. Collisional processes involving the metastable 6s5d [sup 3]D[sub J] levels of barium. United States: N. p., 1993. Web.
Ehrlacher, E A. Collisional processes involving the metastable 6s5d [sup 3]D[sub J] levels of barium. United States.
Ehrlacher, E A. 1993. "Collisional processes involving the metastable 6s5d [sup 3]D[sub J] levels of barium". United States.
@article{osti_7003901,
title = {Collisional processes involving the metastable 6s5d [sup 3]D[sub J] levels of barium},
author = {Ehrlacher, E A},
abstractNote = {The authors have studied a number of collisional processes involving the metastable 6s5d [sup 3]D[sub J] levels of barium. The metastable levels were populated through optical pumping of the 6s[sup 2] [sup 1]S[sub 0] [yields] 6s6p [sup 3]P[sup 0][sub 1] intercombination transition at 791.13 nm, followed by either spontaneous or stimulated decay into the [sup 3]D[sub 1,2] levels. Collisional mixing further redistributed population over the three [sup 3]D[sub J] levels. The authors measured line shapes and foreign-gas broadening rates for the 6s5d [sup 3]D[sub 1] [yields] 5d6p [sup 1]D[sup 0][sub 2], 6s5d [sup 3]D[sub 2] [yields] 5d6p [sup 3]F[sub 3], and 6s5d [sup 3]D[sub 3] [yields] 5d6p [sup 3]F[sub 4] transitions by using a cw pump laser to populate the metastable levels and monitoring the absorption of a weak cw probe laser. In additions, line shapes and broadening rates were also measured for the 6s[sup 2] [sup 1]S[sub 0] [yields] 6s6p [sup 1]P[sup 0][sub 1] resonance and 6s[sup 2] [sup 1]S[sub 0] [yields] 6s6p [sup 3]P[sup 0][sub 1] intercombination transitions. Using the broadening rate coefficients determined for these transitions, they were able to accurately estimate the total number density of barium atoms in the heat-pipe oven, as well as the number density of atoms in the metastable levels when optically pumping the vapor. The authors estimate that 60% of the barium atoms were pumped into the metastable levels using 200 mW of cw laser power. They have also developed a useful technique for studying time-resolved line shapes that combines the time resolution capabilities of a pulsed laser with the frequency resolution of a narrowband, single-mode cw laser. With this technique, they have measured time-dependent line shapes for transitions involving metastable levels using a pulsed pump laser and a cw probe. A comparison of the pulsed and cw line shapes indicates that experimental conditions are below the threshold where Stark broadening is significant.},
doi = {},
url = {https://www.osti.gov/biblio/7003901}, journal = {},
number = ,
volume = ,
place = {United States},
year = {Fri Jan 01 00:00:00 EST 1993},
month = {Fri Jan 01 00:00:00 EST 1993}
}

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