# Global fit to scattering data with next-to-leading logarithmic BFKL resummations

## Abstract

We calculate deep inelastic scattering (DIS) scheme splitting and coefficient functions for electromagnetic DIS with small x resummations, as given by the next-to-leading-logarithmic Balitsky-Fadin-Kuraev-Lipatov (NLL BFKL) equation with running coupling and approximate NLL resummed impact factors. The resummations are combined with a next-to-leading order (NLO) fixed-order expansion, and the improved quantities thus obtained are stable at small x and significantly suppressed with respect to leading logarithmic (LL) results. These results are implemented in a global fit to DIS and related data, and the results compared to a NLO fixed-order DIS scheme fit and with a previous LL resummed fit. The NLL resummed fit quality is excellent and constitutes a marked improvement over the purely fixed-order approach. The input gluon, at Q{sub 0}{sup 2}=1 GeV{sup 2}, obtained from the resummed fit is positive and slightly increasing as x{yields}0, in contrast to the result obtained at fixed order. A resummed prediction for the longitudinal structure function F{sub L} is presented. It is positive definite and growing with energy at low x and Q{sup 2}, where the fixed-order results show a significant perturbative instability.

- Authors:

- NIKHEF, Kruislaan 409, 1098 SJ Amsterdam (Netherlands)
- Department of Physics and Astronomy, University College London, Gower Street, London, WC1E 6BT (United Kingdom)

- Publication Date:

- OSTI Identifier:
- 21010981

- Resource Type:
- Journal Article

- Resource Relation:
- Journal Name: Physical Review. D, Particles Fields; Journal Volume: 75; Journal Issue: 3; Other Information: DOI: 10.1103/PhysRevD.75.034005; (c) 2007 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; COUPLING; DEEP INELASTIC SCATTERING; ELECTROMAGNETIC INTERACTIONS; FOUR MOMENTUM TRANSFER; GLUONS; PARTICLE KINEMATICS; PERTURBATION THEORY; QUANTUM CHROMODYNAMICS; STRUCTURE FUNCTIONS

### Citation Formats

```
White, C. D., and Thorne, R. S.
```*Global fit to scattering data with next-to-leading logarithmic BFKL resummations*. United States: N. p., 2007.
Web. doi:10.1103/PHYSREVD.75.034005.

```
White, C. D., & Thorne, R. S.
```*Global fit to scattering data with next-to-leading logarithmic BFKL resummations*. United States. doi:10.1103/PHYSREVD.75.034005.

```
White, C. D., and Thorne, R. S. Thu .
"Global fit to scattering data with next-to-leading logarithmic BFKL resummations". United States.
doi:10.1103/PHYSREVD.75.034005.
```

```
@article{osti_21010981,
```

title = {Global fit to scattering data with next-to-leading logarithmic BFKL resummations},

author = {White, C. D. and Thorne, R. S.},

abstractNote = {We calculate deep inelastic scattering (DIS) scheme splitting and coefficient functions for electromagnetic DIS with small x resummations, as given by the next-to-leading-logarithmic Balitsky-Fadin-Kuraev-Lipatov (NLL BFKL) equation with running coupling and approximate NLL resummed impact factors. The resummations are combined with a next-to-leading order (NLO) fixed-order expansion, and the improved quantities thus obtained are stable at small x and significantly suppressed with respect to leading logarithmic (LL) results. These results are implemented in a global fit to DIS and related data, and the results compared to a NLO fixed-order DIS scheme fit and with a previous LL resummed fit. The NLL resummed fit quality is excellent and constitutes a marked improvement over the purely fixed-order approach. The input gluon, at Q{sub 0}{sup 2}=1 GeV{sup 2}, obtained from the resummed fit is positive and slightly increasing as x{yields}0, in contrast to the result obtained at fixed order. A resummed prediction for the longitudinal structure function F{sub L} is presented. It is positive definite and growing with energy at low x and Q{sup 2}, where the fixed-order results show a significant perturbative instability.},

doi = {10.1103/PHYSREVD.75.034005},

journal = {Physical Review. D, Particles Fields},

number = 3,

volume = 75,

place = {United States},

year = {Thu Feb 01 00:00:00 EST 2007},

month = {Thu Feb 01 00:00:00 EST 2007}

}