Ba(6[ital s]6[ital p] [sup 1][ital P][sub 1,][ital m[ital j]])[r arrow]Ba(6[ital s]6[ital p] [sup 3][ital P][sub 2,][ital m[ital j]][sup [prime]]) Zeeman cross sections in single collisions with N[sub 2], O[sub 2], and H[sub 2]

Journal Article · Fri Jan 01 00:00:00 EST 1993 · Physical Review A; (United States)

DOI:https://doi.org/10.1103/PhysRevA.47.241· OSTI ID:6942012

Mestdagh, J; Meynadier, P; de Pujo, P; Sublemontier, O; Visticot, J; Berlande, J; Cuvellier, J; Gustavsson, T ^[1]; Suits, A G; Lee, Y T ^[2]

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1. Service des Photons, Atomes et Molecules, Centre d'Etudes Nucleaires de Saclay, 91191 Gif-sur-Yvette CEDEX (France)
2. Department of Chemistry, University of California, Berkeley, California 94720 (United States) Chemical Sciences Division, Lawrence Berkeley Laboratory, University of California, Berkeley, California 94720 (United States)

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. The 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.

• OSTI ID: 6942012
• Journal Information: Physical Review A; (United States), Journal Name: Physical Review A; (United States) Vol. 47:1; ISSN 1050-2947; ISSN PLRAAN
• Country of Publication: United States
• Language: English

Related Subjects

664300* -- Atomic & Molecular Physics-- Collision Phenomena-- (1992-)
74 ATOMIC AND MOLECULAR PHYSICS
ALKALINE EARTH METALS
ATOM COLLISIONS
ATOM-MOLECULE COLLISIONS
BARIUM
COLLISIONS
CROSS SECTIONS
ELEMENTS
HYDROGEN
MAGNETIC FIELDS
METALS
MOLECULE COLLISIONS
NITROGEN
NONMETALS
ORIENTATION
OXYGEN
SPIN ORIENTATION
ZEEMAN EFFECT