Mr
Zhiqing Philippe Zhang
(Laboratoire de l'Accรฉlรฉrateur Linรฉaire (FR))
05/07/2012, 09:00
Track 6. QCD, Jets, Parton Distributions
Parallel Sessions
The inclusive eยฑp single and double differential cross sections for neutral and charged current processes are measured with the H1 detector at HERA. The data were taken at a centre-of-mass energy of โs = 319 GeV with a total integrated luminosity of 329.1 pbโ1 shared between two lepton beam charges and two longitudinal lepton polarisation modes. The differential cross sections are measured in...
05/07/2012, 09:15
Track 6. QCD, Jets, Parton Distributions
Parallel Sessions
The cross sections for neutral current deep inelastic scattering in e+p collisions with a longitudinally polarised positron beam have been measured using the ZEUS detector at HERA. The single-differential cross-sections dsigma/dQ2, dsigma/dx and dsigma/dy and the double-differential cross sections in Q2 and x are measured in the kinematic region Q2 > 185 GeV2 for both positively and negatively...
Dr
Ringaile Placakyte
(DESY (DE))
05/07/2012, 09:30
Track 6. QCD, Jets, Parton Distributions
Parallel Sessions
A preliminary global NLO QCD analysis of the HERA data is presented. The following data sets are used in this analysis:
the NC and CC inclusive DIS cross sections obtained from the combination of the measurements from H1 and ZEUS based on HERA I and HERA II data at the nominal proton beam energy, the preliminary combined inclusive NC DIS cross sections at reduced proton beam energies, the...
Prof.
M. Beatriz Gay Ducati
(Universidade Federal do Rio Grande do Sul (BR))
05/07/2012, 09:45
Track 6. QCD, Jets, Parton Distributions
Parallel Sessions
We show how the AGBS model, originally developed for deep inelastic scattering applied to HERA data on the proton structure function, can also describe the RHIC data on single inclusive hadron yield for $d+Au$ and $p+p$ collisions through a new simultaneous fit. The single inclusive hadron production is modeled through the color glass condensate, which uses the quark(and gluon)--condensate...
Dr
Abilio De Freitas
(DESY Zeuthen (DE))
05/07/2012, 10:00
Track 6. QCD, Jets, Parton Distributions
Parallel Sessions
We report on recent results obtained for the 3-loop heavy flavor Wilson coefficients in deep-inelastic scattering at general values of the Mellin variable N at large scales of Q^2. These concern contributions to the gluonic ladder-topologies, the transition matrix elements in the variable flavor scheme, and first results on higher topologies. The knowledge of the heavy flavor Wilson...
Prof.
Claudia Beatriz Glasman Kuguel
(Universidad Autonoma de Madrid (ES))
05/07/2012, 10:15
Track 6. QCD, Jets, Parton Distributions
Parallel Sessions
The Large Hadron electron Collider (LHeC) is a proposed facility which will exploit the new world of energy and intensity offered by the LHC through collisions with a new 60 GeV electron beam. This contribution summarises the detailed simulation studies on QCD-related topics included in the recently released Conceptual Design Report. Highlights include a new level of precision and flavour...
Prof.
Michael Strauss
(University of Oklahoma (US))
05/07/2012, 11:00
Track 6. QCD, Jets, Parton Distributions
Parallel Sessions
We present two sets of measurements based on data collected with the D0 detector at the Fermilab Tevatron collider running at sqrt(s)=1.96 TeV. First we present a comprehensive study of the differential cross sections for the production of W bosons in association with up to four hadronic jets. Results are compared with the latest NLO and resummation theoretical predictions as well as with...
Dr
Konstantinos Vellidis
(Fermi National Accelerator Laboratory (US))
05/07/2012, 11:15
Track 6. QCD, Jets, Parton Distributions
Parallel Sessions
Inclusive Z boson plus jets cross sections, as well as bottom jet production in association with a Z-boson cross sections, are measured in a final state where the Z boson has decayed in two muons or electrons. Results are based on the full data sample collected with the CDF detector in Run II, corresponding to $\sim 9.4$ fb$ ^{-1}$ of $\rm p\bar{p}$ collisions at $\rm \sqrt{s}$ = 1.96 TeV....
Dr
Jonathan Anderson
(Universitรคt Zรผrich (CH))
05/07/2012, 11:30
Track 6. QCD, Jets, Parton Distributions
Parallel Sessions
We report the results of several analyses based on the reconstruction of electroweak gauge bosons at LHCb. The forward coverage of the LHCb detector provides unique sensitivity to various different observables that can be used to test the Standard Model predictions. The results include those on W and Z production, Z production with associated jets, and low-mass Drell-Yan production.
Prof.
Pierre-Hugues Beauchemin
(Tufts University (US))
05/07/2012, 11:45
Track 6. QCD, Jets, Parton Distributions
Parallel Sessions
The production of jets and/or heavy flavours in association with a W or Z boson represents an important process with which to study QCD in a multi-scale environment. Unprecedented precision is achieved in measurements of differential cross sections and multiplicities, and comparisons are made to state-of-the-art high NLO QCD calculations of high-multiplicity final states. Jets containing b- or...
Dr
Piergiulio Lenzi
(CERN)
05/07/2012, 12:00
Track 6. QCD, Jets, Parton Distributions
Parallel Sessions
The associated production of jets and vector bosons allows for stringent tests of perturbative QCD calculations and is sensitive to the possible presence of new physics beyond the Standard Model. A measurement of jet production rates in association with W and Z bosons, or photons, in proton-proton collisions at a 7 TeV center-of-mass energy is presented, using data collected with the CMS...
Dr
Maarten Boonekamp
(CEA - Centre d'Etudes de Saclay (FR))
05/07/2012, 12:15
Track 6. QCD, Jets, Parton Distributions
Parallel Sessions
Precise measurements of W and Z production, differential in pT and rapidity, are shown. These provide stringent tests of higher order QCD, resummed calculations and non-perturbative models. They are also used to extract information on the strange quark content of the proton.
05/07/2012, 14:00
Track 6. QCD, Jets, Parton Distributions
Parallel Sessions
Isolated-photon+jet production in ep collisions at a centre-of-mass energy of 318 GeV has been measured with the ZEUS detector at HERA using an integrated luminosity of up to 300 pb-1. Measurements of prompt-photon+jet cross sections are presented as functions of the photon transverse energy and pseudorapidity in a wide range of exchanged-photon virtuality. In addition, differential gamma+jet...
Prof.
Ahmed Ali
(DESY (DE))
05/07/2012, 14:15
Track 6. QCD, Jets, Parton Distributions
Parallel Sessions
We compute the transverse energy-energy correlation (EEC) and its asymmetry (AEEC) in next-to-leading order (NLO) in $\alpha_s$ in proton-proton collisions at the LHC with the center-of-mass energy $E_{\rm c.m.}=7$ TeV. We show that the transverse EEC and the AEEC distributions are insensitive to the factorization- and renormalization scales, the underlying minimum bias events, and the...
Mr
Bertrand Chapleau
(McGill University (CA))
05/07/2012, 14:30
Track 6. QCD, Jets, Parton Distributions
Parallel Sessions
Comprehensive jet cross section measurements are presented, spanning the dijet mass range from 70 GeV to 5 TeV. In addition, event shapes constructed from jets are measured, as well as measurements of jets containing charm and beauty hadrons. These measurements constitute precision tests of QCD in a new energy regime, and show sensitivity to the parton densities in the proton and to the value...
Mr
Sanmay Ganguly
(Tata Institute of Fundamental Research)
05/07/2012, 14:45
Track 6. QCD, Jets, Parton Distributions
Parallel Sessions
We present studies of the substructure in multijet and V+jets events at CMS. Several jet grooming techniques are investigated, and We present measurements of jet properties and jet production rates at CMS with pp collisions at 7 TeV. Inclusive jet and dijet differential cross sections are compared to NLO QCD predictions with various PDF sets. We also present studies of the jet substructure in...
Dr
Anastasia Grebenyuk
(DESY (DE))
05/07/2012, 15:00
Track 6. QCD, Jets, Parton Distributions
Parallel Sessions
Scaled momentum distributions for the strange hadrons K0s and Lambda/Lambdabar were measured in deep inelastic ep scattering with the ZEUS detector at HERA using an integrated luminosity of 330 pb-1. The evolution of these distributions with the photon virtuality, Q2, was studied in the kinematic region 10 < Q2 < 40000 GeV2 and 0.001 < x < 0.75, where x is the Bjorken scaling variable. Clear...
Prof.
Richard Dryden Field
(University of Florida (US))
05/07/2012, 15:15
Track 6. QCD, Jets, Parton Distributions
Parallel Sessions
We study the behavior of the underlying event in proton-antiproton collisions at 300 GeV, 900 GeV, and 1.96 TeV using charged particles measured by the CDF detector. The charged particle density and the scalar PTsum density in the transverse region as defined by the leading charged particle, PTmax, are examined as a function of PTmax at the three center-of-mass energies. The data at 300 GeV...
Prof.
Leif Ingvar Lรถnnblad
(Lund University (SE))
05/07/2012, 16:00
Track 6. QCD, Jets, Parton Distributions
Parallel Sessions
LHC is now entering a precision era. No striking signals of new phenomena have yet been found, and the searches now have to focus on very small deviations from the Standard Model. This requires an unprecedented precision in our understanding of the Standard Model. Even though the experiments are extremely ingenious in finding model-independent ways of determining the background, this is not...
Dr
David Kosower
(CEA - Centre d'Etudes de Saclay (FR))
05/07/2012, 16:15
Track 6. QCD, Jets, Parton Distributions
Parallel Sessions
Calculations to next-to-leading order in QCD of Standard-Model processes provide the leading quantitatively reliable predictions. They are a prerequisite for comparisons to experimental data. The
BlackHat collaboration has been pushing the high-multiplicity frontier in such calculations. In this talk, representing the BlackHat collaboration, I present the next-to-leading predictions for W...
Prof.
Bennie Ward
(Baylor University (US))
05/07/2012, 16:30
Track 6. QCD, Jets, Parton Distributions
Parallel Sessions
We present the interplay between the new IR-improved DGLAP-CS theory and the precision of NLO parton shower/ME matched MC`s as it is realized by the new MC Herwiri1.031 in interface to MC@NLO. We discuss phenomenological implications using comparisons with recent LHC data on single heavy gauge boson production.
Dr
Robert Ciesielski
(Rockefeller University (US))
05/07/2012, 16:45
Track 6. QCD, Jets, Parton Distributions
Parallel Sessions
We present the MBR (Minimum Bias Rockefeller) Monte Carlo simulation of (anti)proton-proton interactions and its implementation in the PYTHIA8 event generator. We discuss the total, elastic, and total-inelastic cross sections, and three contributions from diffraction dissociation processes that contribute to the latter: single diffraction, double diffraction, and central diffraction or...
Dr
Marek Schoenherr
(University of Durham (UK))
05/07/2012, 17:00
Track 6. QCD, Jets, Parton Distributions
Parallel Sessions
Similarities and differences between the MC@NLO and the POWHEG methods for matching NLO calculations to parton showers are discussed. Particular emphasis is put on their respective formal accuracies. Implementations of both methods in the SHERPA event generator framework are employed to assess their impact on representative observables. Some freedoms in both formulations will be exploited to...
Prof.
Lance Dixon
(SLAC National Accelerator Laboratory (US))
05/07/2012, 17:15
Track 6. QCD, Jets, Parton Distributions
Parallel Sessions
The prediction of backgrounds to new physics signals in topologies
with large missing transverse energy and jets is important to new physics searches at the LHC. The BlackHat collaboration has investigated theoretical issues in extrapolating backgrounds from experimental control regions to signal regions. For example, we compute, ratios of gamma + n-jet to Z + n-jet production rates and...
