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arXiv · 1011.0606

Correlation Widths in Quantum--Chaotic Scattering

B. Dietz·A. Richter·H. A. Weidenmueller
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Abstract

An important parameter to characterize the scattering matrix S for quantum-chaotic scattering is the width Gamma_{corr} of the S-matrix autocorrelation function. We show that the "Weisskopf estimate" d/(2pi) sum_c T_c (where d is the mean resonance spacing, T_c with 0 <= T_c <= 1 the "transmission coefficient" in channel c and where the sum runs over all channels) provides a very good approximation to Gamma_{corr} even when the number of channels is small. That same conclusion applies also to the cross-section correlation function.

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B. Dietz, A. Richter, H. A. Weidenmueller. 2010-11-02. Correlation Widths in Quantum--Chaotic Scattering. https://doi.org/10.1016/j.physletb.2011.02.009

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