Repository logo
 

Utilising optimised operators and distillation to extract scattering phase shifts

Published version
Peer-reviewed

Type

Conference Object

Change log

Authors

Woss, AJ 
Thomas, CE 

Abstract

In this investigation, we examine how the precision of energy spectra and scattering phase shifts, extracted in lattice QCD, depend upon the degree of distillation type smearing. We use the variational method to extract energy spectra for the isospin-1, JPC = 1−− channel and use the Lüscher method to compute scattering amplitudes, relevant for the ρ resonance, in ππ elastic scattering. Optimised interpolating operators for a single ground state pion are constructed and these are used to construct two pion operators. Calculations are performed on an anisotropic lattice with a pion mass of mπ = 236MeV. We provide a comprehensive comparison of energy spectra and scattering phase shifts across distillation spaces of varying rank.

Description

Keywords

hep-lat, hep-lat

Journal Title

34th annual International Symposium on Lattice Field Theory

Conference Name

34th annual International Symposium on Lattice Field Theory

Journal ISSN

1824-8039

Volume Title

Publisher

Proceedings of Science
Sponsorship
Science and Technology Facilities Council (ST/L000385/1)
STFC (1628534)
AW is supported by the U.K. Science and Technology Facilities Council (STFC). CET acknowledges support from STFC [grant ST/L000385/1]. Computations were performed at Jefferson Laboratory under the USQCD Initiative and the LQCD ARRA project. The software codes Chroma, QUDA, QPhiX, and QOPQDP were used to compute the propagators required for this project. This research was supported in part under an ALCC award, and used resources of the Oak Ridge Leadership Computing Facility at the Oak Ridge National Laboratory, which is supported by the Office of Science of the U.S. Department of Energy under Contract No. DE-AC05-00OR22725. This research is also part of the Blue Waters sustained-petascale computing project, which is supported by the National Science Foundation (awards OCI-0725070 and ACI-1238993) and the state of Illinois. Blue Waters is a joint effort of the University of Illinois at Urbana-Champaign and its National Center for Supercomputing Applications. This work is also part of the PRAC “Lattice QCD on Blue Waters”. This research used resources of the National Energy Research Scientific Computing Center (NERSC), a DOE Office of Science User Facility supported by the Office of Science of the U.S. Department of Energy under Contract No. DEAC02-05CH11231. The authors acknowledge the Texas Advanced Computing Center (TACC) at The University of Texas at Austin for providing HPC resources that have contributed to the research results reported within this paper. Gauge configurations were generated using resources awarded from the U.S. Department of Energy INCITE program at the Oak Ridge Leadership Computing Facility, the NERSC, the NSF Teragrid at the TACC and the Pittsburgh Supercomputer Center, as well as at Jefferson Lab.