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arXiv · 1811.10750

$K π$ scattering and the $K^*(892)$ resonance in 2+1 flavor QCD

Gumaro Rendon·Luka Leskovec·Stefan Meinel·John Negele·Srijit Paul·Marcus Petschlies·Andrew Pochinsky·Giorgio Silvi·Sergey Syritsyn
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Abstract

In this project, we will compute the form factors relevant for $B \to K^*(\to K π)\ell^+\ell^-$ decays. To map the finite-volume matrix elements computed on the lattice to the infinite-volume $B \to K π$ matrix elements, the $K π$ scattering amplitude needs to be determined using Lüscher's method. Here we present preliminary results from our calculations with $2+1$ flavors of dynamical clover fermions. We extract the $P$-wave scattering phase shifts and determine the $K^*$ resonance mass and the $K^* K π$ coupling for two different ensembles with pion masses of $317(2)$ and $178(2)$ MeV.

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Gumaro Rendon, Luka Leskovec, Stefan Meinel, John Negele, Srijit Paul, Marcus Petschlies, Andrew Pochinsky, Giorgio Silvi, Sergey Syritsyn. 2019-01-23. $K π$ scattering and the $K^*(892)$ resonance in 2+1 flavor QCD. https://arxiv.org/abs/1811.10750

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