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Reflection Approximation in Photoassociation Spectroscopy



C Boisseau, E Audouard, J Vigue, Paul S. Julienne


We construct an analytical wavefunction in the phase-amplitude formalism to describe collisions between two neutral atoms. This wavefunction is valid from intermediate to asymptotic internuclear distance over a large energy range near zero energy; and is especially suitable for cold and ultracold collisions. We have used this analytic wavefunction with the reflection approximation formula for calculating Franck-Condon factors for photoassociative spectroscopy. Numerical tests show very satisfactory agreement between the resulting analytic formula and the fully quantum numerical results in most cases investigated. Finally, we show in a model case that our analytical wavefunction enables us to relate the scattering length directly to a preasymptotic node in the ground state wavefunction, which in principle could be measured by photoassociative spectroscopy.
Physical Review A (Atomic, Molecular and Optical Physics)


analytic wavefunction, cold atom collisions, Franck-Condon factors, photoassociation spectroscopy, reflection approximation


Boisseau, C. , Audouard, E. , Vigue, J. and Julienne, P. (2000), Reflection Approximation in Photoassociation Spectroscopy, Physical Review A (Atomic, Molecular and Optical Physics) (Accessed March 4, 2024)
Created October 31, 2000, Updated October 12, 2021