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Title: Direct Photon Production at Next-to–Next-to-Leading Order

Authors:
; ;
Publication Date:
Sponsoring Org.:
USDOE
OSTI Identifier:
1361002
Grant/Contract Number:
AC02-07CH11359
Resource Type:
Journal Article: Publisher's Accepted Manuscript
Journal Name:
Physical Review Letters
Additional Journal Information:
Journal Volume: 118; Journal Issue: 22; Related Information: CHORUS Timestamp: 2017-05-31 22:10:13; Journal ID: ISSN 0031-9007
Publisher:
American Physical Society
Country of Publication:
United States
Language:
English

Citation Formats

Campbell, John M., Ellis, R. Keith, and Williams, Ciaran. Direct Photon Production at Next-to–Next-to-Leading Order. United States: N. p., 2017. Web. doi:10.1103/PhysRevLett.118.222001.
Campbell, John M., Ellis, R. Keith, & Williams, Ciaran. Direct Photon Production at Next-to–Next-to-Leading Order. United States. doi:10.1103/PhysRevLett.118.222001.
Campbell, John M., Ellis, R. Keith, and Williams, Ciaran. Wed . "Direct Photon Production at Next-to–Next-to-Leading Order". United States. doi:10.1103/PhysRevLett.118.222001.
@article{osti_1361002,
title = {Direct Photon Production at Next-to–Next-to-Leading Order},
author = {Campbell, John M. and Ellis, R. Keith and Williams, Ciaran},
abstractNote = {},
doi = {10.1103/PhysRevLett.118.222001},
journal = {Physical Review Letters},
number = 22,
volume = 118,
place = {United States},
year = {Wed May 31 00:00:00 EDT 2017},
month = {Wed May 31 00:00:00 EDT 2017}
}

Journal Article:
Free Publicly Available Full Text
This content will become publicly available on May 31, 2018
Publisher's Accepted Manuscript

Citation Metrics:
Cited by: 6works
Citation information provided by
Web of Science

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  • We present the first calculation of direct photon production at next-to-next-to leading order (NNLO) accuracy in QCD. For this process, although the final state cuts mandate only the presence of a single electroweak boson, the underlying kinematics resembles that of a generic vector boson plus jet topology. In order to regulate the infrared singularities present at this order we use the $N$-jettiness slicing procedure, applied for the first time to a final state that at Born level includes colored partons but no required jet. We compare our predictions to ATLAS 8 TeV data and find that the inclusion of themore » NNLO terms in the perturbative expansion, supplemented by electroweak corrections, provides an excellent description of the data with greatly reduced theoretical uncertainties.« less
  • For large-[ital p][sub [ital T]] direct photon production by a longitudinally polarized beam and target complete next-to-leading-order corrections [higher-order corrections (HOC's)] are determined. For these, one loop corrections to the basic subprocesses [ital [rvec g]] [ital [rvec q]][r arrow][gamma][ital q] and [ital [rvec q]] [bar [rvec q]][r arrow][gamma][ital g], as well as the contributions of [ital [rvec g]] [ital [rvec g]][r arrow][gamma][ital q[bar q]] and [ital [rvec q]] [ital [rvec q]][r arrow][gamma][ital qq], are calculated. For [ital [rvec p]] [ital [rvec p]][r arrow][gamma]+[ital X], [ital K] factors greater than unity and polarized cross sections and asymmetries well measurable are obtained.more » Certain differences in the regularization procedures and the question of dominance of HOC's by soft, collinear, and virtual gluons are also discussed.« less
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