Nucleon structure functions with domain wall fermions
Abstract
We present a quenched lattice QCD calculation of the first few moments of the polarized and unpolarized structure functions of the nucleon. Our calculations are done using domain wall fermions and the DBW2 gauge action with inverse lattice spacing a{sup 1}{approx_equal}1.3 GeV, physical volume V{approx_equal}(2.4 fm){sup 3}, and light quark masses down to about 1/4 the strange quark mass (m{sub {pi}}{approx_equal}400 MeV). Values of the individual moments are found to be significantly larger than experiment, as in past lattice calculations, but interestingly the chiral symmetry of domain wall fermions allows for a precise determination of the ratio of the flavor nonsinglet momentum fraction to the helicity distribution, <x>{sub ud}/<x>{sub {delta}}{sub u{delta}{sub d}}, which is in very good agreement with experiment. We discuss the implications of this result. Next, we show that the chiral symmetry of domain wall fermions is useful in eliminating mixing of power divergent lower dimensional operators with twist3 operators. Finally, we compute the isovector tensor charge at renormalization scale {mu}=2 GeV in the MS scheme, <1>{sub {delta}}{sub u{delta}}{sub d}=1.192(30), where the error is the statistical error only.
 Authors:
 CTP/LNS, Room 6304, Massachusetts Institute of Technology, 77 Massachusetts Ave., Cambridge, Massachusetts 021394307 (United States)
 RIKENBNL Research Center, Brookhaven National Laboratory, Upton, New York 11973 (United States)
 (United States)
 Institute for Particle and Nuclear Studies, KEK, Tsukuba, Ibaraki, 3050801 (Japan)
 (SOKENDAI), Tsukuba, Ibaraki 3050801 (Japan)
 Publication Date:
 OSTI Identifier:
 20783005
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Physical Review. D, Particles Fields; Journal Volume: 73; Journal Issue: 9; Other Information: DOI: 10.1103/PhysRevD.73.094503; (c) 2006 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; CHIRAL SYMMETRY; D QUARKS; DISTRIBUTION; FLAVOR MODEL; GEV RANGE; HELICITY; ISOVECTORS; LATTICE FIELD THEORY; MEV RANGE; NUCLEONS; QUANTUM CHROMODYNAMICS; RENORMALIZATION; REST MASS; S QUARKS; STRUCTURE FUNCTIONS; U QUARKS; WALLS
Citation Formats
Orginos, K., Blum, T., Physics Department, University of Connecticut, Storrs, Connecticut 062693046, Ohta, S., Graduate University for Advanced Studies, and RIKENBNL Research Center, Brookhaven National Laboratory, Upton, New York 11973. Nucleon structure functions with domain wall fermions. United States: N. p., 2006.
Web. doi:10.1103/PHYSREVD.73.094503.
Orginos, K., Blum, T., Physics Department, University of Connecticut, Storrs, Connecticut 062693046, Ohta, S., Graduate University for Advanced Studies, & RIKENBNL Research Center, Brookhaven National Laboratory, Upton, New York 11973. Nucleon structure functions with domain wall fermions. United States. doi:10.1103/PHYSREVD.73.094503.
Orginos, K., Blum, T., Physics Department, University of Connecticut, Storrs, Connecticut 062693046, Ohta, S., Graduate University for Advanced Studies, and RIKENBNL Research Center, Brookhaven National Laboratory, Upton, New York 11973. Mon .
"Nucleon structure functions with domain wall fermions". United States.
doi:10.1103/PHYSREVD.73.094503.
@article{osti_20783005,
title = {Nucleon structure functions with domain wall fermions},
author = {Orginos, K. and Blum, T. and Physics Department, University of Connecticut, Storrs, Connecticut 062693046 and Ohta, S. and Graduate University for Advanced Studies and RIKENBNL Research Center, Brookhaven National Laboratory, Upton, New York 11973},
abstractNote = {We present a quenched lattice QCD calculation of the first few moments of the polarized and unpolarized structure functions of the nucleon. Our calculations are done using domain wall fermions and the DBW2 gauge action with inverse lattice spacing a{sup 1}{approx_equal}1.3 GeV, physical volume V{approx_equal}(2.4 fm){sup 3}, and light quark masses down to about 1/4 the strange quark mass (m{sub {pi}}{approx_equal}400 MeV). Values of the individual moments are found to be significantly larger than experiment, as in past lattice calculations, but interestingly the chiral symmetry of domain wall fermions allows for a precise determination of the ratio of the flavor nonsinglet momentum fraction to the helicity distribution, <x>{sub ud}/<x>{sub {delta}}{sub u{delta}{sub d}}, which is in very good agreement with experiment. We discuss the implications of this result. Next, we show that the chiral symmetry of domain wall fermions is useful in eliminating mixing of power divergent lower dimensional operators with twist3 operators. Finally, we compute the isovector tensor charge at renormalization scale {mu}=2 GeV in the MS scheme, <1>{sub {delta}}{sub u{delta}}{sub d}=1.192(30), where the error is the statistical error only.},
doi = {10.1103/PHYSREVD.73.094503},
journal = {Physical Review. D, Particles Fields},
number = 9,
volume = 73,
place = {United States},
year = {Mon May 01 00:00:00 EDT 2006},
month = {Mon May 01 00:00:00 EDT 2006}
}

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