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arXiv · 2102.00914

The $\Lambda(1405)$ in resummed chiral effective field theory

X. -L. Ren·E. Epelbaum·J. Gegelia·Ulf-G. Meißner
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Abstract

We study the unitarized meson-baryon scattering amplitude at leading order in the strangeness $S=-1$ sector using time-ordered perturbation theory for a manifestly Lorentz-invariant formulation of chiral effective field theory. By solving the coupled-channel integral equations with the full off-shell dependence of the effective potential and applying subtractive renormalization, we analyze the renormalized scattering amplitudes and obtain the two-pole structure of the $\Lambda(1405)$ resonance. We also point out the necessity of including higher-order terms.

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X. -L. Ren, E. Epelbaum, J. Gegelia, Ulf-G. Meißner. 2021-02-01. The $\Lambda(1405)$ in resummed chiral effective field theory. https://doi.org/10.1140/epjc%2Fs10052-021-09386-0

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