Improved adiabatic calculation of muonic-hydrogen-atom cross sections. III. Hyperfine transitions in asymmetric collisions

Journal Article · Sun Sep 01 04:00:00 EDT 1991 · Physical Review A. General Physics; (United States)

DOI:https://doi.org/10.1103/PhysRevA.44.2836· OSTI ID:5253784

Cohen, J S ^[1]

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1. Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico (USA)

Cross sections for transitions between hyperfine-structure states of muonic hydrogen atoms in asymmetric collisions have been calculated. The interaction is described by the improved adiabatic representation. {ital s} waves dominate the cross sections except for the remarkable case of {ital t}{mu}({up arrow}{up arrow})+{ital d} where the {ital p} wave dominates even at liquid-hydrogen temperature. The quenching rates for the colli-sions in which the muon resides on the heavier isotope are {lambda}({ital d}{mu}({up arrow}{up arrow}) +{ital p}{r arrow}{ital d}{mu}({up arrow}{down arrow})+{ital p}) =5.5{times}10{sup 2} (6.4{times}10{sup 2}) s{sup {minus}1}, {lambda}({ital t}{mu}({up arrow}{up arrow})+{ital p}{r arrow}{ital t}{mu}({up arrow}{down arrow})+{ital p})=3.1{times}10{sup 2} (3.2{times}10{sup 2}) s{sup {minus}1}, and {lambda}({ital t}{mu}({up arrow}{up arrow}) +{ital d} {r arrow}{ital t}{mu}({up arrow}{down arrow})+{ital d})=7.5{times}10{sup 1} (7.3{times}10{sup 2}) s{sup {minus}1} at 23 K (232 K) and liquid-hydrogen density. Although some experimental observations have been attributed to hyperfine quenching in asymmetric collisions, these rates are probably too slow to have had an effect in previous experiments. However, the rate for {ital t}{mu}({up arrow}{up arrow})+{ital d} is somewhat uncertain since it is found to be extraordinarily sensitive to the potential. As a by-product of this work, an independent value of the hyperfine correction to the binding energy of {ital td}{mu}({ital J}=1,{ital v}=1) is obtained: {Delta}{var epsilon}{sub hfs}={minus}36.1 meV for the lowest hyperfine state.

• OSTI ID: 5253784
• Journal Information: Physical Review A. General Physics; (United States), Journal Name: Physical Review A. General Physics; (United States) Vol. 44:5; ISSN 1050-2947; ISSN PLRAA
• Country of Publication: United States
• Language: English

Related Subjects

640303* -- Atomic
Molecular & Chemical Physics-- Positronium
Muonium
& Muonic & Mesic Atoms & Molecules
74 ATOMIC AND MOLECULAR PHYSICS
ASYMMETRY
ATOMS
CALCULATION METHODS
CROSS SECTIONS
ELEMENTS
ENERGY-LEVEL TRANSITIONS
HYDROGEN
HYPERFINE STRUCTURE
MUONIC ATOMS
NONMETALS