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arXiv · 1511.02275

Low energy scattering phase shifts for meson-baryon systems

William Detmold·Amy Nicholson
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Abstract

In this work, we calculate meson-baryon scattering phase shifts in four channels using lattice QCD methods. From a set of calculations at four volumes, corresponding to spatial sizes of 2, 2.5, 3, and 4 fm, and a pion mass of m_pi ~ 390 MeV, we determine the scattering lengths and effective ranges for these systems at the corresponding quark masses. We also perform the calculation at a lighter quark mass, m_pi ~ 230 MeV, on the largest volume. Using these determinations, along with those in previous work, we perform a chiral extrapolation of the scattering lengths to the physical point after correcting for the effective range contributions using the multi-volume calculations performed at m_pi ~ 390 MeV.

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BibTeXRIS

William Detmold, Amy Nicholson. 2016-06-27. Low energy scattering phase shifts for meson-baryon systems. https://doi.org/10.1103/physrevd.93.114511

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