Main Image
Volume 363 - 37th International Symposium on Lattice Field Theory (LATTICE2019) - Main session
I=3/2Nπ scattering and the ∆(1232) resonance on $N_f=2+1$ CLS ensembles using the stochastic LapH method
C.W. Andersen,* J. Bulava, B. Hörz, C. Morningstar
*corresponding author
Full text: pdf
Pre-published on: 2020 January 03
Published on:
Calculations of the elastic $I=\frac{3}{2}$ nucleon-pion scattering phase shifts on two lattice QCD ensembles with $m_\pi=200\mathrm{MeV}$ and $280\mathrm{MeV}$ are presented. The ensembles both employ $N_\mathrm{f} = 2+1$ Wilson clover fermions. We determine the $\Delta(1232)$ resonance parameters from a finite volume scattering analysis. In one study the single partial wave simplification is employed to compute the $p$-wave amplitude while in the other we treat the partial wave mixing between $s$- and $p$-wave contributions. Fitting our data to a Breit-Wigner resonance model we find $m_\Delta/m_\pi = 7.13(9)$ and $4.75(5)$ on the two ensembles respectively, showing that for a lighter quark mass the resonance mass moves from near the $N\pi$ threshold to near the $N\pi\pi$ threshold, in agreement with experiment.
Open Access
Creative Commons LicenseCopyright owned by the author(s) under the term of the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.