# 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 u-d}/<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 twist-3 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 6-304, Massachusetts Institute of Technology, 77 Massachusetts Ave., Cambridge, Massachusetts 02139-4307 (United States)
- RIKEN-BNL Research Center, Brookhaven National Laboratory, Upton, New York 11973 (United States)
- (United States)
- Institute for Particle and Nuclear Studies, KEK, Tsukuba, Ibaraki, 305-0801 (Japan)
- (SOKENDAI), Tsukuba, Ibaraki 305-0801 (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 06269-3046, Ohta, S., Graduate University for Advanced Studies, and RIKEN-BNL 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 06269-3046, Ohta, S., Graduate University for Advanced Studies, & RIKEN-BNL 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 06269-3046, Ohta, S., Graduate University for Advanced Studies, and RIKEN-BNL 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 06269-3046 and Ohta, S. and Graduate University for Advanced Studies and RIKEN-BNL 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 u-d}/<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 twist-3 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}

}