TY - EJOUR AU - Bulava, John AU - Cid-Mora, Bárbara AU - Hanlon, Andrew D. AU - Hörz, Ben AU - Mohler, Daniel AU - Morningstar, Colin AU - Moscoso, Joseph AU - Nicholson, Amy AU - Romero-López, Fernando AU - Skinner, Sarah AU - Walker-Loud, André TI - The two-pole nature of the Λ(1405) from lattice QCD IS - arXiv:2307.10413 M1 - PUBDB-2023-04594 M1 - arXiv:2307.10413 M1 - MIT-CTP/5579 PY - 2023 N1 - 7 pages, 4 figures, and 1 table. added some references and revised introduction AB - This letter presents the first lattice QCD computation of the coupled channel πΣ\unicodex2013―KN scattering amplitudes at energies near 1405 MeV. These amplitudes contain the resonance Λ(1405) with strangeness S=−1 and isospin, spin, and parity quantum numbers I(J<sup>P</sup>)=0(1/2<sup>−</sup>). However, whether there is a single resonance or two nearby resonance poles in this region is controversial theoretically and experimentally. Using single-baryon and meson-baryon operators to extract the finite-volume stationary-state energies to obtain the scattering amplitudes at slightly unphysical quark masses corresponding to m<sub>π</sub> ≈ 200 MeV and m<sub>K</sub> ≈ 487 MeV, this study finds the amplitudes exhibit a virtual bound state below the πΣ threshold in addition to the established resonance pole just below the ―KN threshold. Several parametrizations of the two-channel K-matrix are employed to fit the lattice QCD results, all of which support the two-pole picture suggested by SU(3) chiral symmetry and unitarity. KW - resonance, pole (INSPIRE) KW - quark, mass (INSPIRE) KW - symmetry, chiral (INSPIRE) KW - lattice field theory (INSPIRE) KW - scattering amplitude (INSPIRE) KW - Lambda(1405) (INSPIRE) KW - parity (INSPIRE) KW - strangeness (INSPIRE) KW - unitarity (INSPIRE) KW - quantum number (INSPIRE) KW - parametrization (INSPIRE) KW - meson baryon (INSPIRE) KW - bound state (INSPIRE) KW - coupled channel (INSPIRE) KW - SU(3) (INSPIRE) KW - isospin (INSPIRE) KW - spin (INSPIRE) KW - finite size (INSPIRE) LB - PUB:(DE-HGF)25 DO - DOI:10.3204/PUBDB-2023-04594 UR - https://bib-pubdb1.desy.de/record/587898 ER -