Speaker
Description
A lattice QCD computation of the I=0 and S=-1 coupled channel \pi \Sigma - K N scattering amplitudes in the Λ(1405)region is detailed. We use a single ensemble of gauge field configurations with N_f = 2+ 1 dynamical quark flavors where the mass of the pion is around 200 MeV. Hermitian correlation matrices using both single baryon and meson-baryon interpolating operators for a variety of different total momenta and irreducible representations are used. Several parametrizations of the two-channel scattering K-matrix are utilized to obtain the scattering amplitudes from the finite-volume spectrum. I will discuss the results obtained for the complex scattering amplitudes in this calculation and the strategies utilized to verify the two-pole nature of the Lambda(1405) resonance.
