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Feshbach Spectroscopy of a Shape Resonance

Thomas Volz·Stephan Dürr·Niels Syassen·Gerhard Rempe·Eric van Kempen·Servaas Kokkelmans
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Abstract

We present a new spectroscopy technique for studying cold-collision properties. The technique is based on the association and dissociation of ultracold molecules using a magnetically tunable Feshbach resonance. The energy and lifetime of a shape resonance are determined from a measurement of the dissociation rate. Additional spectroscopic information is obtained from the observation of a spatial interference pattern between an outgoing s wave and d wave. The experimental data agree well with the results from a new model, in which the dissociation process is connected to a scattering gedanken experiment, which is analyzed using a coupled-channels calculation.

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Thomas Volz, Stephan Dürr, Niels Syassen, Gerhard Rempe, Eric van Kempen, Servaas Kokkelmans. 2005-05-05. Feshbach Spectroscopy of a Shape Resonance. https://doi.org/10.1103/physreva.72.010704

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