Title: Controlling excited-state contributions with distillation in lattice QCD calculations of nucleon isovector charges $g_S^{u-d}$ , $g_A^{u-d}$ , $g_T^{u-d}$

Abstract

Here, we investigate the application of the distillation smearing approach, and the use of the variational method with an extended basis of operators facilitated by this approach, on the calculation of the nucleon isovector charges $$g_S^{u-d}$$, $$g_A^{u-d}$$, and $$g_T^{u-d}$$. We find that the better sampling of the lattice enabled through the use of distillation yields a substantial reduction in the statistical uncertainty in comparison with the use of alternative smearing methods, and furthermore, appears to offer better control over the contribution of excited-states compared to use of a single, local interpolating operator. The additional benefit arising through the use of the variational method in the distillation approach is less dramatic, but nevertheless significant given that it requires no additional Dirac inversions.

Authors:

Egerer, Colin; Richards, David; Winter, Frank

Publication Date:

Tue Feb 19 00:00:00 EST 2019

Research Org.:

Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States)

Sponsoring Org.:

USDOE Office of Science (SC), Nuclear Physics (NP)

OSTI Identifier:

1495062

Alternate Identifier(s):

OSTI ID: 1496580

Report Number(s):

JLAB-THY-18-2857; DOE/OR/23177-4572; arXiv:1810.09991
Journal ID: ISSN 2470-0010; PRVDAQ; 034506

Grant/Contract Number:  

AC05-06OR23177; FG02-04ER41302; SC0014664

Resource Type:

Published Article

Journal Name:

Physical Review D

Additional Journal Information:

Journal Name: Physical Review D Journal Volume: 99 Journal Issue: 3; Journal ID: ISSN 2470-0010

Publisher:

American Physical Society

Country of Publication:

United States

Language:

English

Subject:

73 NUCLEAR PHYSICS AND RADIATION PHYSICS