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arXiv · 1310.4958

K pi scattering in moving frames

C. B. Lang·Luka Leskovec·Daniel Mohler·Sasa Prelovsek
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Abstract

We extend our study of the $Kπ$ system to moving frames and present an exploratory extraction of the masses and widths for the $K^*$ resonances by simulating $Kπ$ scattering in p-wave with $I=1/2$ on the lattice. Using $Kπ$ systems with non-vanishing total momenta allows the extraction of phase shifts at several values of $Kπ$ relative momenta. A Breit-Wigner fit of the phase renders a $K^*(892)$ resonance mass and $K^*\to K π$ coupling compatible with the experimental numbers. We also determine the $K^*(1410)$ mass assuming the experimental $K^*(1410)$ width. We contrast the resonant $I=1/2$ channel with the repulsive non-resonant $I=3/2$ channel, where the phase is found to be negative and small, in agreement with experiment.

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C. B. Lang, Luka Leskovec, Daniel Mohler, Sasa Prelovsek. 2013-10-18. K pi scattering in moving frames. https://arxiv.org/abs/1310.4958

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