Low-energy pion-nucleon scattering and the Δ resonance in lattice QCD

¹ Computation-based Science and Technology Research Center, The Cyprus Institute
² Department of Physics, University of Cyprus, POB 20537, 1678 Nicosia, Cyprus
³ Faculty of Mathematics und Natural Sciences, University of Wuppertal
⁴ Institute for Advanced Simulation, Forschungszentrum Jülich GmbH, Jülich 52425, Germany
⁵ Theory Center, Jefferson Lab, Newport News, VA 23606, USA
⁶ Department of Physics, University of Arizona, Tucson, AZ 85721, USA
⁷ Center for Theoretical Physics, Massachusetts Institute of Technology
⁸ Helmholtz-Institut für Strahlen- und Kernphysik
⁹ Bethe-Center for Theoretical Physics
¹⁰ Department of Physics and Astronomy, Stony Brook University, Stony Brook, NY 11794, USA

^* Corresponding author: alexand@ucy.ac.cy
^** Corresponding author: koutsou@cyi.ac.cy
^*** Corresponding author: s.krieg@fz-juelich.de
^**** Corresponding author: leskovec@jlab.org
^† Corresponding author: smeinel@email.arizona.edu
^‡ Corresponding author: negele@mit.edu
^₧ Corresponding author: s.paul@hpc-leap.eu
^¶ Corresponding author: marcus.petschlies@hiskp.uni-bonn.de
^║ Corresponding author: avp@mit.edu
^** Corresponding author: jgrs@email.arizona.edu
^†† Corresponding author: g.silvi@fz-juelich.de
^‡‡ Corresponding author: ssyritsyn@quark.phy.bnl.gov

Published online: 22 September 2020

Abstract

We report on our investigation of low-energy pion-nucleon scattering from lattice QCD with Wilson type fermions. Our focus is on the isospin I = 3/2 channel, which couples to the Delta resonance. We discuss our calculations aiming at the extraction of the Delta resonance mass, width and effective coupling at pion mass 250 MeV, using the Lüscher finite-volume method to extract the phase shift δ_J=3/2,l=1.