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Title: Measurement of the lifetimes of the lowest {sup 3}P{sub 1} state of neutral Ba and Ra

Abstract

The lifetimes of the lowest {sup 3}P{sub 1} states of Ba and Ra were determined to be 1345{+-}14 ns and 422{+-}20 ns, respectively, by measuring the exponential decay of fluorescence after illuminating a thermal atomic beam with pulses of laser light. In addition, the {sup 1}S{sub 0}(F=1/2)-{sup 3}P{sub 1}(F=3/2) transition frequency in {sup 225}Ra was measured to be 13 999.269{+-}0.001 cm{sup -1} by referencing a nearby I{sub 2} transition.

Authors:
; ; ; ; ; ; ;  [1];  [2];  [1];  [3]
  1. Physics Division, Argonne National Laboratory, Argonne, Illinois 60439 (United States)
  2. Chemical Engineering Division, Argonne National Laboratory, Argonne, Illinois 60439 (United States)
  3. (United States)
Publication Date:
OSTI Identifier:
20786622
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. A; Journal Volume: 73; Journal Issue: 1; Other Information: DOI: 10.1103/PhysRevA.73.010501; (c) 2006 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
74 ATOMIC AND MOLECULAR PHYSICS; ATOMIC BEAMS; BARIUM; DECAY; FLUORESCENCE; IODINE; LASER RADIATION; LIFETIME; P STATES; PULSES; RADIUM; RADIUM 225

Citation Formats

Scielzo, N. D., Guest, J. R., Schulte, E. C., Ahmad, I., Bailey, K., Holt, R. J., O'Connor, T. P., Potterveld, D. H., Bowers, D. L., Lu, Z.-T., and Department of Physics and the Enrico Fermi Institute, The University of Chicago, Chicago, Illinois 60637. Measurement of the lifetimes of the lowest {sup 3}P{sub 1} state of neutral Ba and Ra. United States: N. p., 2006. Web. doi:10.1103/PHYSREVA.73.0.
Scielzo, N. D., Guest, J. R., Schulte, E. C., Ahmad, I., Bailey, K., Holt, R. J., O'Connor, T. P., Potterveld, D. H., Bowers, D. L., Lu, Z.-T., & Department of Physics and the Enrico Fermi Institute, The University of Chicago, Chicago, Illinois 60637. Measurement of the lifetimes of the lowest {sup 3}P{sub 1} state of neutral Ba and Ra. United States. doi:10.1103/PHYSREVA.73.0.
Scielzo, N. D., Guest, J. R., Schulte, E. C., Ahmad, I., Bailey, K., Holt, R. J., O'Connor, T. P., Potterveld, D. H., Bowers, D. L., Lu, Z.-T., and Department of Physics and the Enrico Fermi Institute, The University of Chicago, Chicago, Illinois 60637. Sun . "Measurement of the lifetimes of the lowest {sup 3}P{sub 1} state of neutral Ba and Ra". United States. doi:10.1103/PHYSREVA.73.0.
@article{osti_20786622,
title = {Measurement of the lifetimes of the lowest {sup 3}P{sub 1} state of neutral Ba and Ra},
author = {Scielzo, N. D. and Guest, J. R. and Schulte, E. C. and Ahmad, I. and Bailey, K. and Holt, R. J. and O'Connor, T. P. and Potterveld, D. H. and Bowers, D. L. and Lu, Z.-T. and Department of Physics and the Enrico Fermi Institute, The University of Chicago, Chicago, Illinois 60637},
abstractNote = {The lifetimes of the lowest {sup 3}P{sub 1} states of Ba and Ra were determined to be 1345{+-}14 ns and 422{+-}20 ns, respectively, by measuring the exponential decay of fluorescence after illuminating a thermal atomic beam with pulses of laser light. In addition, the {sup 1}S{sub 0}(F=1/2)-{sup 3}P{sub 1}(F=3/2) transition frequency in {sup 225}Ra was measured to be 13 999.269{+-}0.001 cm{sup -1} by referencing a nearby I{sub 2} transition.},
doi = {10.1103/PHYSREVA.73.0},
journal = {Physical Review. A},
number = 1,
volume = 73,
place = {United States},
year = {Sun Jan 15 00:00:00 EST 2006},
month = {Sun Jan 15 00:00:00 EST 2006}
}
  • The lifetimes of the lowest {sup 3}P{sub 1} states of Ba and Ra were determined to be 1345 {+-} 14 ns and 422 {+-} 20 ns, respectively, by measuring the exponential decay of fluorescence after illuminating a thermal atomic beam with pulses of laser light. In addition, the {sup 1}S{sub 0}(F=1/2)-{sup 3}P{sub 1}(F=3/2) transition frequency in {sup 225}Ra was measured to be 13 999.269 {+-} 0.001 cm{sup -1} by referencing a nearby I{sub 2} transition.
  • Various electronic states of Ba, from ground state up to 2.24 eV ({sup 1}S{sub 0}, {sup 3}D{sub J}, {sup 1}D{sub 2}, {sup 3}P{sub 1}, and {sup 1}P{sub 1}) together with Ba{sup +}({sup 2}P{sub 3/2}), were produced by 1064 nm high-irradiance pulsed nanosecond laser ablation of Ba in vacuum. The velocity distribution for every species was obtained from time-of-flight measurements, using pulsed laser induced fluorescence or time-resolved optical emission spectroscopy, as applicable to each species. The distributions are bimodal, Maxwell-Boltzmann functions for {sup 1}S{sub 0}, {sup 3}D{sub J}, and {sup 1}D{sub 2} and shifted Maxwell-Boltzmann for the rest of the states,more » with different peak velocities and average, hyperthermal translational temperatures. Possible mechanisms for the production of these velocity distributions are discussed.« less
  • The beam foil technique has been used to study the lifetimes of the 4d{sup 9}5p levels in Ag II, Cd III, and In IV in the Pd isoelectronic sequence. The latest work in In IV confirms general isoelectronic trends in the lifetimes of the 4d{sup 9}5p levels exhibited by the ions studied earlier. The In IV system was studied at 480 keV, made possible by the Toledo 330 keV heavy ion accelerator, coupled with a doubly ionized In beam. The Tl II level was studied at 520 keV by similar means; higher energy was used to minimize beam divergence andmore » extend the foil life as much as possible. Similar techniques have been applied to Bi II.« less
  • Zeeman cross sections [sigma][sub [ital j],][ital m[ital j]][r arrow][ital j][prime],[ital m][sub [ital j]][sup [prime]] for the spin-changing 6[ital s]6[ital p] [sup 1][ital P][sub 1]--6[ital s]6[ital p] [sup 3][ital P][sub 2] transition of barium induced by single collisions with N[sub 2], O[sub 2], and H[sub 2] have been measured using a crossed-beam apparatus. State-selective preparation of 6[ital s]6[ital p] [sup 1][ital P][sub 1,][ital m[ital j]] and detection of 6[ital s]6[ital p] [sup 3][ital P][sub 2,][ital m[ital j]][sup [prime]] was achieved using the laser excitation technique in the presence of a magnetic field that breaks the degeneracy of the magnetic sublevels. Themore » results showed that the Zeeman cross sections [sigma]([sup 1][ital P][sub 1,][ital m[ital j]][r arrow][sup 3][ital P][sub 2,][ital m[ital j]][sup [prime]]) are fairly dependent upon [ital m][sub [ital j]] and [ital m][sub [ital j]][sup [prime]] for N[sub 2] and H[sub 2], whereas the Zeeman cross sections all have the same value with O[sub 2]. Additionally the flux-velocity contour map of Ba(6[ital s]6[ital p] [sup 3][ital P][sub 2]) for scattering with H[sub 2] depends significantly upon the magnetic sublevel of barium in the exit channel. The results for Ba-(N[sub 2],H[sub 2]) scattering were accounted for semiquantitatively by a very simple model. The model was then used to stress which physical phenomena are at the origin of the preservation of the orbital alignment and orientation during collisions. The present work also compared the kind of information obtained by the direct measurement of Zeeman cross sections to that found in other experiments that deal with the effect of polarizing the collision partners.« less