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arXiv · 1712.10141

Scattering amplitude from Bethe-Salpeter wave function inside the interaction range

Yusuke Namekawa·Takeshi Yamazaki
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Abstract

We propose a method to calculate scattering amplitudes using the Bethe-Salpeter wave function inside the interaction range on the lattice. For an exploratory study of this method, we evaluate a scattering length of $I=2$ S-wave two pions by the use of the on-shell scattering amplitude. Our result is confirmed to be consistent with the value obtained from the conventional finite volume method. The half-off-shell scattering amplitude is also evaluated.

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Yusuke Namekawa, Takeshi Yamazaki. 2018-08-08. Scattering amplitude from Bethe-Salpeter wave function inside the interaction range. https://doi.org/10.1103/physrevd.98.011501

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