Jet pair production in POWHEG

  • Simone Alioli
  • Keith Hamilton
  • Paolo Nason
  • Carlo Oleari
  • Emanuele Re
Open Access


We present an implementation of the next-to-leading order dijet production process in hadronic collisions in the framework of POWHEG, which is a method to implement NLO calculations within a shower Monte Carlo context. In constructing the simulation, we have made use of the POWHEG BOX toolkit, which makes light of many of the most technical steps. The majority of this article is concerned with the study of the predictions of the Monte Carlo simulation. In so doing, we validate our program for use in experimental analyses, elaborating on some of the more subtle features which arise from the interplay of the NLO and resummed components of the calculation. We conclude our presentation by comparing predictions from the simulation against a number of Tevatron and LHC jet-production results.


Jets NLO Computations Hadronic Colliders QCD 


  1. [1]
    ATLAS collaboration, G. Aad et al., Measurement of inclusive jet and dijet cross sections in proton-proton collisions at 7 TeV centre-of-mass energy with the ATLAS detector, Eur. Phys. J. C 71 (2011) 1512 [arXiv:1009.5908] [SPIRES].ADSGoogle Scholar
  2. [2]
    CMS collaboration, V. Khachatryan et al., Search for Dijet Resonances in 7 TeV pp Collisions at CMS, Phys. Rev. Lett. 105 (2010) 211801 [arXiv:1010.0203] [SPIRES].ADSCrossRefGoogle Scholar
  3. [3]
    U. Baur, I. Hinchliffe and D. Zeppenfeld, Excited Quark Production at Hadron Colliders, Int. J. Mod. Phys. A 2 (1987) 1285 [SPIRES].ADSGoogle Scholar
  4. [4]
    S. Cullen, M. Perelstein and M.E. Peskin, TeV strings and collider probes of large extra dimensions, Phys. Rev. D 62 (2000) 055012 [hep-ph/0001166] [SPIRES].ADSGoogle Scholar
  5. [5]
    L.A. Anchordoqui et al., Dijet signals for low mass strings at the LHC, Phys. Rev. Lett. 101 (2008) 241803 [arXiv:0808.0497] [SPIRES].ADSCrossRefGoogle Scholar
  6. [6]
    S. Frixione and B.R. Webber, Matching NLO QCD computations and parton shower simulations, JHEP 06 (2002) 029 [hep-ph/0204244] [SPIRES].ADSCrossRefGoogle Scholar
  7. [7]
    P. Nason, A new method for combining NLO QCD with shower Monte Carlo algorithms, JHEP 11 (2004) 040 [hep-ph/0409146] [SPIRES].ADSCrossRefGoogle Scholar
  8. [8]
    S. Frixione, P. Nason and C. Oleari, Matching NLO QCD computations with Parton Shower simulations: the POWHEG method, JHEP 11 (2007) 070 [arXiv:0709.2092] [SPIRES].ADSCrossRefGoogle Scholar
  9. [9]
    S. Frixione, F. Stoeckli, P. Torrielli, B.R. Webber and C.D. White, The MCaNLO 4.0 Event Generator, arXiv:1010.0819 [SPIRES].
  10. [10]
    M. Bahr et al., HERWIG++ Physics and Manual, Eur. Phys. J. C 58 (2008) 639 [arXiv:0803.0883] [SPIRES].ADSCrossRefGoogle Scholar
  11. [11]
    S. Hoche, F. Krauss, M. Schonherr and F. Siegert, Automating the POWHEG method in Sherpa, arXiv:1008.5399 [SPIRES].
  12. [12]
    The processes implemented so far in the POWHEG BOX are available at the svn repository: svn://
  13. [13]
    S. Alioli, P. Nason, C. Oleari and E. Re, A general framework for implementing NLO calculations in shower Monte Carlo programs: the POWHEG BOX, JHEP 06 (2010) 043 [arXiv:1002.2581] [SPIRES].ADSCrossRefGoogle Scholar
  14. [14]
    S. Frixione and G. Ridolfi, Jet photoproduction at HERA, Nucl. Phys. B 507 (1997) 315 [hep-ph/9707345] [SPIRES].ADSCrossRefGoogle Scholar
  15. [15]
    S. Frixione, Z. Kunszt and A. Signer, Three jet cross-sections to next-to-leading order, Nucl. Phys. B 467 (1996) 399 [hep-ph/9512328] [SPIRES].ADSCrossRefGoogle Scholar
  16. [16]
    S. Frixione, A General approach to jet cross-sections in QCD, Nucl. Phys. B 507 (1997) 295 [hep-ph/9706545] [SPIRES].ADSCrossRefGoogle Scholar
  17. [17]
    R.K. Ellis and J.C. Sexton, QCD radiative corrections to parton-parton scattering, Nucl. Phys. B 269 (1986) 445 [SPIRES].ADSCrossRefGoogle Scholar
  18. [18]
    Z. Kunszt and D.E. Soper, Calculation of jet cross-sections in hadron collisions at order α s 3, Phys. Rev. D 46 (1992) 192 [SPIRES].ADSGoogle Scholar
  19. [19]
    R.K. Ellis, G. Marchesini and B.R. Webber, Soft Radiation in Parton Parton Scattering, Nucl. Phys. B 286 (1987) 643 [SPIRES].ADSCrossRefGoogle Scholar
  20. [20]
    G. ’t Hooft, A planar diagram theory for strong interactions, Nucl. Phys. B 72 (1974) 461 [SPIRES].ADSCrossRefGoogle Scholar
  21. [21]
    G. Marchesini and B.R. Webber, Monte Carlo Simulation of General Hard Processes with Coherent QCD Radiation, Nucl. Phys. B 310 (1988) 461 [SPIRES].ADSCrossRefGoogle Scholar
  22. [22]
    S. Alioli, P. Nason, C. Oleari and E. Re, Vector boson plus one jet production in POWHEG, JHEP 01 (2011) 095 [arXiv:1009.5594] [SPIRES].ADSCrossRefGoogle Scholar
  23. [23]
    G.C. Blazey et al., Run II jet physics, hep-ex/0005012 [SPIRES].
  24. [24]
    J. Pumplin et al., New generation of parton distributions with uncertainties from global QCD analysis, JHEP 07 (2002) 012 [hep-ph/0201195] [SPIRES].ADSCrossRefGoogle Scholar
  25. [25]
    M. Cacciari and G.P. Salam, Dispelling the N 3 myth for the k T jet-finder, Phys. Lett. B 641 (2006) 57 [hep-ph/0512210] [SPIRES].ADSGoogle Scholar
  26. [26]
    M. Cacciari, G.P. Salam and G.Soyez,
  27. [27]
    G.P. Salam and G. Soyez, A practical Seedless Infrared-Safe Cone jet algorithm, JHEP 05 (2007) 086 [arXiv:0704.0292] [SPIRES].ADSCrossRefGoogle Scholar
  28. [28]
    S.D. Ellis and D.E. Soper, Successive combination jet algorithm for hadron collisions, Phys. Rev. D 48 (1993) 3160 [hep-ph/9305266] [SPIRES].ADSGoogle Scholar
  29. [29]
    S. Catani, Y.L. Dokshitzer, M.H. Seymour and B.R. Webber, Longitudinally invariant k T clustering algorithms for hadron-hadron collisions, Nucl. Phys. B 406 (1993) 187 [SPIRES].ADSCrossRefGoogle Scholar
  30. [30]
    P. Nason, MINT: a Computer Program for Adaptive Monte Carlo Integration and Generation of Unweighted Distributions, arXiv:0709.2085 [SPIRES].
  31. [31]
    CDF collaboration, T. Aaltonen et al., Measurement of the Inclusive Jet Cross section at the Fermilab Tevatron \( p\bar{p} \) Collider Using a Cone-Based Jet Algorithm, Phys. Rev. D 78 (2008) 052006 [arXiv:0807.2204] [SPIRES].ADSGoogle Scholar
  32. [32]
    M. Klasen and G. Kramer, Dijet cross-sections at O(αα S 2) in photon-proton collisions, Phys. Lett. B 366 (1996) 385 [hep-ph/9508337] [SPIRES].ADSGoogle Scholar
  33. [33]
    A. Banfi and M. Dasgupta, Dijet rates with symmetric E T cuts, JHEP 01 (2004) 027 [hep-ph/0312108] [SPIRES].ADSCrossRefGoogle Scholar
  34. [34]
    D0 collaboration, V.M. Abazov et al., Measurement of the dijet invariant mass cross section in proton anti-proton collisions at \( \sqrt {s} = 1.96\;TeV \), Phys. Lett. B 693 (2010) 531 [arXiv:1002.4594] [SPIRES].ADSGoogle Scholar
  35. [35]
    M. Rubin, G.P. Salam and S. Sapeta, Giant QCD K-factors beyond NLO, JHEP 09 (2010) 084 [arXiv:1006.2144] [SPIRES].ADSCrossRefGoogle Scholar
  36. [36]
    S. Alioli, P. Nason, C. Oleari and E. Re, NLO Higgs boson production via gluon fusion matched with shower in POWHEG, JHEP 04 (2009) 002 [arXiv:0812.0578] [SPIRES].ADSCrossRefGoogle Scholar
  37. [37]
    K. Hamilton, P. Richardson and J. Tully, A Positive-Weight Next-to-Leading Order Monte Carlo Simulation for Higgs Boson Production, JHEP 04 (2009) 116 [arXiv:0903.4345] [SPIRES].ADSCrossRefGoogle Scholar
  38. [38]
    T. Sjöstrand, S. Mrenna and P.Z. Skands, PYTHIA 6.4 Physics and Manual, JHEP 05 (2006) 026 [hep-ph/0603175] [SPIRES].ADSCrossRefGoogle Scholar
  39. [39]
    G. Corcella et al., HERWIG 6.5: an event generator for Hadron Emission Reactions With Interfering Gluons (including supersymmetric processes), JHEP 01 (2001) 010 [hep-ph/0011363] [SPIRES].ADSCrossRefGoogle Scholar
  40. [40]
    G. Corcella et al., HERWIG 6.5 release note, hep-ph/0210213 [SPIRES].
  41. [41]
    E. Boos et al., Generic user process interface for event generators, hep-ph/0109068 [SPIRES].
  42. [42]
    J. Alwall et al., A standard format for Les Houches event files, Comput. Phys. Commun. 176 (2007) 300 [hep-ph/0609017] [SPIRES].ADSCrossRefGoogle Scholar
  43. [43]
    K. Hamilton, P. Richardson and J. Tully, A Positive-Weight Next-to-Leading Order Monte Carlo Simulation of Drell-Yan Vector Boson Production, JHEP 10 (2008) 015 [arXiv:0806.0290] [SPIRES].ADSCrossRefGoogle Scholar
  44. [44]
    T. Sjöstrand and P.Z. Skands, Multiple interactions and the structure of beam remnants, JHEP 03 (2004) 053 [hep-ph/0402078] [SPIRES].ADSCrossRefGoogle Scholar
  45. [45]
    CDF–Run II collaboration, A. Abulencia et al., Measurement of the Inclusive Jet Cross section using the k T algorithm in \( p\bar{p} \) collisions at \( \sqrt {s} = 1.96\;TeV \) with the CDF II Detector, Phys. Rev. D 75 (2007) 092006 [hep-ex/0701051] [SPIRES].ADSGoogle Scholar
  46. [46]
    D0 collaboration, V.M. Abazov et al., Measurement of dijet azimuthal decorrelations at central rapidities in \( p\bar{p} \) collisions at \( \sqrt {s} = 1.96\;TeV \), Phys. Rev. Lett. 94 (2005) 221801 [hep-ex/0409040] [SPIRES].ADSCrossRefGoogle Scholar
  47. [47]
    CDF collaboration, F. Abe et al., Evidence for color coherence in \( p\bar{p} \) collisions at \( \sqrt {s} = 1.8\;TeV \), Phys. Rev. D 50 (1994) 5562 [SPIRES].ADSGoogle Scholar
  48. [48]
    M. Cacciari, G.P. Salam and G. Soyez, The anti-k T jet clustering algorithm, JHEP 04 (2008) 063 [arXiv:0802.1189] [SPIRES].ADSCrossRefGoogle Scholar

Copyright information

© The Author(s) 2011

Open Access This article is distributed under the terms of the Creative Commons Attribution License which permits any use, distribution and reproduction in any medium, provided the original author(s) and source are credited.

Authors and Affiliations

  • Simone Alioli
    • 1
  • Keith Hamilton
    • 2
  • Paolo Nason
    • 2
  • Carlo Oleari
    • 3
  • Emanuele Re
    • 4
  1. 1.Deutsches Elektronen-Synchrotron DESYZeuthenGermany
  2. 2.INFN, Sezione di Milano-BicoccaMilanItaly
  3. 3.Università di Milano-Bicocca and INFN, Sezione di Milano-BicoccaMilanItaly
  4. 4.Institute for Particle Physics Phenomenology, Department of PhysicsUniversity of DurhamDurhamU.K.

Personalised recommendations