# Extrapolating $W$ -associated jet-production ratios at the LHC

## Abstract

Electroweak vector-boson production, accompanied by multiple jets, is an important background to searches for physics beyond the standard model. A precise and quantitative understanding of this process is helpful in constraining deviations from known physics. We study four key ratios in W + n -jet production at the LHC. We compute the ratio of cross sections for W + n - to W + (n-1)-jet production as a function of the minimum jet transverse momentum. We also study the ratio differentially, as a function of the W-boson transverse momentum; as a function of the scalar sum of the jet transverse energy, H$$jets\atop{T}$$; and as a function of certain jet transverse momenta. We show how to use such ratios to extrapolate differential cross sections to W + 6 -jet production at next-to-leading order, and we cross-check the method against a direct calculation at leading order. We predict the differential distribution in H$$jets\atop{T}$$ for W + 6 jets at next-to-leading order using such an extrapolation. We use the BlackHat software library together with SHERPA to perform the computations.

- Authors:

- Univ. of California, Los Angeles, CA (United States). Dept. of Physics and Astronomy
- SLAC National Accelerator Lab., Menlo Park, CA (United States); Stanford Univ., CA (United States)
- Albert-Ludwigs-Univ. Freiburg, Freiburg (Germany); Univ. Simón Bolívar, Caracas (Venezuela)
- Albert-Ludwigs-Univ. Freiburg, Freiburg (Germany)
- Alternative Energies and Atomic Energy Commission (CEA), Saclay (France). Inst. de Physique Théorique
- Univ. of Durham, Durham (United Kingdom). Dept. of Physics

- Publication Date:

- Research Org.:
- SLAC National Accelerator Lab., Menlo Park, CA (United States)

- Sponsoring Org.:
- USDOE Office of Science (SC), High Energy Physics (HEP) (SC-25)

- OSTI Identifier:
- 1502952

- Alternate Identifier(s):
- OSTI ID: 1198676

- Report Number(s):
- SLAC-PUB-16144

Journal ID: ISSN 1550-7998; PRVDAQ

- Grant/Contract Number:
- AC02-76SF00515; SC0009937; AC02-05CH11231; ERC-AdG-8301; PHY-0705682; PITN-GA-2010-264564

- Resource Type:
- Accepted Manuscript

- Journal Name:
- Physical Review. D, Particles, Fields, Gravitation and Cosmology

- Additional Journal Information:
- Journal Volume: 92; Journal Issue: 1; Journal ID: ISSN 1550-7998

- Publisher:
- American Physical Society (APS)

- Country of Publication:
- United States

- Language:
- English

- Subject:
- 72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS

### Citation Formats

```
Bern, Z., Dixon, L. J., Febres Cordero, F., Höche, S., Ita, H., Kosower, D. A., and Maître, D. Extrapolating W -associated jet-production ratios at the LHC. United States: N. p., 2015.
Web. doi:10.1103/PhysRevD.92.014008.
```

```
Bern, Z., Dixon, L. J., Febres Cordero, F., Höche, S., Ita, H., Kosower, D. A., & Maître, D. Extrapolating W -associated jet-production ratios at the LHC. United States. doi:10.1103/PhysRevD.92.014008.
```

```
Bern, Z., Dixon, L. J., Febres Cordero, F., Höche, S., Ita, H., Kosower, D. A., and Maître, D. Tue .
"Extrapolating W -associated jet-production ratios at the LHC". United States. doi:10.1103/PhysRevD.92.014008. https://www.osti.gov/servlets/purl/1502952.
```

```
@article{osti_1502952,
```

title = {Extrapolating W -associated jet-production ratios at the LHC},

author = {Bern, Z. and Dixon, L. J. and Febres Cordero, F. and Höche, S. and Ita, H. and Kosower, D. A. and Maître, D.},

abstractNote = {Electroweak vector-boson production, accompanied by multiple jets, is an important background to searches for physics beyond the standard model. A precise and quantitative understanding of this process is helpful in constraining deviations from known physics. We study four key ratios in W + n -jet production at the LHC. We compute the ratio of cross sections for W + n - to W + (n-1)-jet production as a function of the minimum jet transverse momentum. We also study the ratio differentially, as a function of the W-boson transverse momentum; as a function of the scalar sum of the jet transverse energy, H$jets\atop{T}$; and as a function of certain jet transverse momenta. We show how to use such ratios to extrapolate differential cross sections to W + 6 -jet production at next-to-leading order, and we cross-check the method against a direct calculation at leading order. We predict the differential distribution in H$jets\atop{T}$ for W + 6 jets at next-to-leading order using such an extrapolation. We use the BlackHat software library together with SHERPA to perform the computations.},

doi = {10.1103/PhysRevD.92.014008},

journal = {Physical Review. D, Particles, Fields, Gravitation and Cosmology},

number = 1,

volume = 92,

place = {United States},

year = {2015},

month = {7}

}

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