Nucleon form factors from quenched lattice QCD with domain wall fermions
Abstract
We present a quenched lattice calculation of the weak nucleon form factors: vector [F{sub V}(q{sup 2})], induced tensor [F{sub T}(q{sup 2})], axial vector [F{sub A}(q{sup 2})] and induced pseudoscalar [F{sub P}(q{sup 2})] form factors. Our simulations are performed on three different lattice sizes L{sup 3}xT=24{sup 3}x32, 16{sup 3}x32, and 12{sup 3}x32 with a lattice cutoff of a{sup 1}{approx_equal}1.3 GeV and light quark masses down to about 1/4 the strange quark mass (m{sub {pi}}{approx_equal}390 MeV) using a combination of the DBW2 gauge action and domain wall fermions. The physical volume of our largest lattice is about (3.6 fm){sup 3}, where the finite volume effects on form factors become negligible and the lower momentum transfers (q{sup 2}{approx_equal}0.1 GeV{sup 2}) are accessible. The q{sup 2} dependences of form factors in the low q{sup 2} region are examined. It is found that the vector, induced tensor, and axialvector form factors are well described by the dipole form, while the induced pseudoscalar form factor is consistent with pionpole dominance. We obtain the ratio of axial to vector coupling g{sub A}/g{sub V}=F{sub A}(0)/F{sub V}(0)=1.219(38) and the pseudoscalar coupling g{sub P}=m{sub {mu}}F{sub P}(0.88m{sub {mu}}{sup 2})=8.15(54), where the errors are statistical errors only. These values agree with experimentalmore »
 Authors:

 Department of Physics, University of Tokyo, Hongo 731, Tokyo 1130033 (Japan)
 Physics Department, University of Connecticut, Storrs, Connecticut 062693046 (United States)
 Publication Date:
 OSTI Identifier:
 21250249
 Resource Type:
 Journal Article
 Journal Name:
 Physical Review. D, Particles Fields
 Additional Journal Information:
 Journal Volume: 78; Journal Issue: 1; Other Information: DOI: 10.1103/PhysRevD.78.014510; (c) 2008 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA); Journal ID: ISSN 05562821
 Country of Publication:
 United States
 Language:
 English
 Subject:
 72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; BETA DECAY; CAPTURE; COUPLING; D QUARKS; DIPOLES; FORM FACTORS; GEV RANGE 0110; GOLDBERGERTREIMAN RELATION; LATTICE FIELD THEORY; MASS; MATRIX ELEMENTS; MEV RANGE 1001000; MOMENTUM TRANSFER; MUONS; NEUTRONS; PIONS; PROTONS; QUANTUM CHROMODYNAMICS; S QUARKS; SIMULATION; U QUARKS
Citation Formats
Sasaki, Shoichi, and Yamazaki, Takeshi. Nucleon form factors from quenched lattice QCD with domain wall fermions. United States: N. p., 2008.
Web. doi:10.1103/PHYSREVD.78.014510.
Sasaki, Shoichi, & Yamazaki, Takeshi. Nucleon form factors from quenched lattice QCD with domain wall fermions. United States. https://doi.org/10.1103/PHYSREVD.78.014510
Sasaki, Shoichi, and Yamazaki, Takeshi. Tue .
"Nucleon form factors from quenched lattice QCD with domain wall fermions". United States. https://doi.org/10.1103/PHYSREVD.78.014510.
@article{osti_21250249,
title = {Nucleon form factors from quenched lattice QCD with domain wall fermions},
author = {Sasaki, Shoichi and Yamazaki, Takeshi},
abstractNote = {We present a quenched lattice calculation of the weak nucleon form factors: vector [F{sub V}(q{sup 2})], induced tensor [F{sub T}(q{sup 2})], axial vector [F{sub A}(q{sup 2})] and induced pseudoscalar [F{sub P}(q{sup 2})] form factors. Our simulations are performed on three different lattice sizes L{sup 3}xT=24{sup 3}x32, 16{sup 3}x32, and 12{sup 3}x32 with a lattice cutoff of a{sup 1}{approx_equal}1.3 GeV and light quark masses down to about 1/4 the strange quark mass (m{sub {pi}}{approx_equal}390 MeV) using a combination of the DBW2 gauge action and domain wall fermions. The physical volume of our largest lattice is about (3.6 fm){sup 3}, where the finite volume effects on form factors become negligible and the lower momentum transfers (q{sup 2}{approx_equal}0.1 GeV{sup 2}) are accessible. The q{sup 2} dependences of form factors in the low q{sup 2} region are examined. It is found that the vector, induced tensor, and axialvector form factors are well described by the dipole form, while the induced pseudoscalar form factor is consistent with pionpole dominance. We obtain the ratio of axial to vector coupling g{sub A}/g{sub V}=F{sub A}(0)/F{sub V}(0)=1.219(38) and the pseudoscalar coupling g{sub P}=m{sub {mu}}F{sub P}(0.88m{sub {mu}}{sup 2})=8.15(54), where the errors are statistical errors only. These values agree with experimental values from neutron {beta} decay and muon capture on the proton. However, the root meansquared radii of the vector, induced tensor, and axial vector underestimate the known experimental values by about 20%. We also calculate the pseudoscalar nucleon matrix element in order to verify the axial WardTakahashi identity in terms of the nucleon matrix elements, which may be called as the generalized GoldbergerTreiman relation.},
doi = {10.1103/PHYSREVD.78.014510},
url = {https://www.osti.gov/biblio/21250249},
journal = {Physical Review. D, Particles Fields},
issn = {05562821},
number = 1,
volume = 78,
place = {United States},
year = {2008},
month = {7}
}