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arXiv · 2108.04712

Fitting ultracold resonances without a fit

Andrea Simoni
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Abstract

We present a numerical procedure allowing one to extract Feshbach resonance parameters from numerical calculations without relying on approximate fitting procedures. Our approach is based on a simple decomposition of the reactance matrix in terms of poles and residual background contribution, and can be applied to the general situation of inelastic overlapping resonances. A simple lineshape for overlapping inelastic resonances, equivalent to known results in the particular cases of isolated and overlapping elastic features, is also rigorously derived.

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Andrea Simoni. 2021-08-10. Fitting ultracold resonances without a fit. https://doi.org/10.1088/1367-2630/ac3442

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