1–5 Sept 2015
Queen Mary University of London
Europe/London timezone

Contribution List

124 out of 124 displayed
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  1. Eram Syed Rizvi (Queen Mary, University of London)
    01/09/2015, 10:00
  2. Prof. Simon Gaskell (Principal QMUL)
    01/09/2015, 10:10
  3. Jonathan Butterworth (University College London (UK))
    01/09/2015, 10:20
  4. Nigel Glover (Durham University)
    01/09/2015, 11:20
  5. Roberta Arcidiacono (Universita Del Piemonte Orientale (IT))
    01/09/2015, 14:00
  6. Richard Dryden Field (University of Florida (US))
    01/09/2015, 14:40
  7. Alessia Bruni (Universita e INFN, Bologna (IT))
    01/09/2015, 15:20
  8. Daniel Britzger (Deutsches Elektronen-Synchrotron Hamburg and Zeuthen (DE))
    01/09/2015, 16:30
    Multi-parton Dynamics
    Diffractive parton densities are derived from inclusive measurements of diffraction at HERA. Their application, interfaced to next-to-leading-orde QCD predictions, to other final states and processes allows the factorisation theorem to be tested in diffractive scattering. The H1 and ZEUS collaborations have made many measurements if different final states, wth the most recent H1 results on...
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  9. David Martin Bjergaard (Duke University (US))
    01/09/2015, 16:30
    Heavy Quarks
    ATLAS has a wide programme to study the production cross section and decay properties of particles with beauty, as well as charmonium and bottomonium states. This presentation will cover ATLAS results in the domain of charmonium production, including J/psi, psi(2s), chi_c and chi_b states as well as the X(3872) resonance, using full Run-1 ATLAS dataset and extending upon previous measurements...
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  10. Hector De La Torre (Universidad Autonoma de Madrid-Unknown-Unknown), Hector De La Torre Perez (Universidad Autonoma de Madrid (ES))
    01/09/2015, 16:30
    Hard QCD
    Cross sections for jet and isolated photon production in pp collisions have been measured by the ATLAS collaboration at 7 and 8 TeV. Double­-differential cross sections for inclusive, di­, and tri­-jet final states are measured and compared to expectations based on next-­to­-leading order QCD calculations as well as to next­-to­-leading order Monte Carlo simulations. First LHC Run­2 results...
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  11. Lucian Harland-Lang (University College London)
    01/09/2015, 16:30
    PDFs
    We present the MMHT14 PDFs, an update of the previous major release in the same framework, i.e. MSTW08. We discuss the changes in both the central values and uncertainties in the PDFs due to changes in theoretical procedures and the impact of new, largely LHC data-sets. We note, however, that changes in predictions are rather small. We discuss the correlation between the PDFs and the...
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  12. Jason Adrian Kamin (University of Illinois at Chicago (US))
    01/09/2015, 16:55
    Heavy Quarks
    Quarkonia are important probes of the quark-gluon plasma since they are produced at early times and propagate through the medium, mapping its evolution. In this talk we present the latest results on quarkonium production in pPb and PbPb collisions from CMS. Selected results from measurements of nuclear modification factors, excited-to-ground state ratios, elliptic flow and forward-backward...
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  13. ALESSANDRA LUCA' (INFN - National Institute for Nuclear Physics), Alessandra Luca
    01/09/2015, 17:00
    Hard QCD
    The production of photons with large transverse energy in hadronic collisions is an important testing ground for perturbative Quantum Chromodynamics (pQCD), enabling to probe parton distribution functions (PDFs) and the parton-to-photon fragmentation functions (FFs). In addition, high-ET photons can also constitute an irreducible background for important searches such as H→γγ, or SUSY and...
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  14. Miguel Ignacio Arratia Munoz (University of Cambridge (GB))
    01/09/2015, 17:00
    Multi-parton Dynamics
    The ATLAS Collaboration has measured the t-­differential elastic pp cross section in a dedicated run at 7 TeV centre­of­-mass energy with the ALFA Roman Pot detector. From the extrapolation to t=0 the total cross section as well as the inelastic cross section are extracted. First LHC Run­2 results will be presented for the measurement of the inelastic pp cross­-section using minimum bias...
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  15. Daniel Stump (Michigan State University)
    01/09/2015, 17:00
    PDFs
    The CTEQ-TEA collaboration has published their next generation global analysis of QCD, with PDFs named CT14 PDFs. The purpose of the talk is to summarize this work, and describe some methods that we use. The talk will include these topics: an overview of the CT14 PDFs; the LHC data, and other new data, that has been used in the CT14 analysis; the impact of CT14 PDFs on predictions for...
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  16. Marco Pappagallo (University of Glasgow (GB))
    01/09/2015, 17:20
    Heavy Quarks
    The latest results on heavy quark spectroscopy from LHCb experiment will be reported, including the studies on excited bottom and charm mesons and charmonium-like exotic states such as X(3872).
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  17. Gudrun Heinrich (Max Planck Institute for Physics)
    01/09/2015, 17:30
    Hard QCD
    New features of the program SecDec will be presented, which allow the numerical calculation of multi-scale loop integrals in a highly efficient way. Results for two-loop integrals with several mass scales will be shown to illustrate some applications of the program.
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  18. Stefano Carrazza (Università degli Studi e INFN Milano (IT))
    01/09/2015, 17:30
    PDFs
    We discuss the effect of the complete leading-order QED corrections to the DGLAP equations in the perturbative evolution of parton distribution functions (PDFs). This requires the extension of the purely QCD DGLAP evolution, including a PDF for the photon and, consistently, also for the charged leptons e±, μ± and τ±. We present the implementation of the QED-corrected DGLAP evolution in the...
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  19. Valentina Cairo (Universita della Calabria (IT))
    01/09/2015, 17:30
    Multi-parton Dynamics
    Measurements of the properties of charged particle production are presented from proton­-proton collisions at different centre­-of­-mass energies in the range of 0.9 to 13 TeV and compared to various Monte Carlo event generator models. Furthermore particle distributions sensitive to the underlying event in proton­-proton collisions have been measured and are compared to theoretical models. The...
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  20. Konstantin Toms (University of New Mexico (US))
    01/09/2015, 17:45
    Heavy Quarks
    We present the latest results from the ATLAS experiment on hadron decays and spectroscopy, including observation of the B_c(2S) state, production of the B_c+ meson, branching ratio measurements of B_c->J/psiD(*), extraction of fragmentation fractions fs/fd via reconstructed Bs->J/psiPhi and Bd->J/psiK* decays, and studies of the decay properties of the Lambda_b. We also present the results of...
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  21. Nicola Adriano Lo Presti (University of Zurich)
    01/09/2015, 17:50
    Hard QCD
    I present recent progress in the calculation of the master integrals for the five-point amplitude at two loops in QCD, which is a crucial contribution to computation of the the next-to-next-to-leading order cross section for three-jet production at the LHC. After a brief review of the differenential-equation method for evaluating Feynman integrals, I will discuss its application to compute...
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  22. David Edwin Bertsche (University of Oklahoma (US))
    01/09/2015, 18:00
    Multi-parton Dynamics
    We present new measurements of the associated production of quarkonium with a vector boson or an additional quarkonium state using the ATLAS Run-1 dataset. These rare processes provide new insight into QCD models of quarkonium production, but also provide new opportunities to study double parton scattering, including cross-section measurements in single and double parton scattering dominated...
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  23. Prof. liuti simonetta
    01/09/2015, 18:00
    PDFs
    I will discuss the application of an alternative type of neural network, the Self-Organizing Maps (SOMs), to extract parton distribution functions from various hard scattering processes. SOMs provide a complementary algorithm to NNPDFs yielding a parametrization that is free from the bias implicit in choosing specific analytic forms. At the same time it enables us to extrapolate to...
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  24. Alexander Ochirov (University of Edinburgh)
    01/09/2015, 18:10
    Hard QCD
    We work out a new color decomposition for tree amplitudes in quantum chromodynamics with flavored quarks in a reduced basis of primitive amplitudes. These primitives, with k quark-antiquark pairs and (n-2k) gluons, are taken in the (n-2)!/k! Melia basis, and are independent under the color-algebra Kleiss-Kuijf relations. This generalizes the color decomposition of Del Duca, Dixon, and Maltoni...
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  25. Matthew David Needham (University of Edinburgh (GB))
    01/09/2015, 18:10
  26. Ansgar Denner (Bayerische Julius Max. Universitaet Wuerzburg (DE))
    02/09/2015, 09:00
  27. Eric Laenen (Nikhef)
    02/09/2015, 09:40
  28. Lauren Alexandra Tompkins (Stanford University (US))
    02/09/2015, 10:20
  29. Sergey Alekhin
    02/09/2015, 11:25
  30. Amanda Sarkar (University of Oxford (GB))
    02/09/2015, 12:05
  31. Paul Richard Newman (University of Birmingham (GB))
    02/09/2015, 12:45
    Heavy Quarks
    The LHeC is a proposed upgrade of the LHC to study ep/eA collisions in the TeV regime, by adding a 60 GeV electron beam through an Energy Recovery Linac. In this talk the project will be briefly reviewed and its current status presented. Then the possibilities for QCD studies: precision proton and nucleus PDFs with complete flavour decomposition for use in hadron colliders, per mille accuracy...
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  32. Alessia Bruni (Universita e INFN, Bologna (IT))
    02/09/2015, 14:10
    Multi-parton Dynamics
    The ratio of the exclusive electroproduction of psi(2S) and J/psi mesons has been measured at HERA. The results are sensitive to the wave functions of the vector mesons and are compared to predictions of QCD-inspired models of vector-meson production. Exclusive dijet production in diffractive deep inelastic scattering has been measured at HERA. Cross sections are presented as a function of...
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  33. Remie Hanna (CEA/IRFU,Centre d'etude de Saclay Gif-sur-Yvette (FR))
    02/09/2015, 14:10
    Several measurements performed by the ATLAS collaboration are either useful to constrain the proton structure or are affected by its associated uncertainties. The strange-quark density is rather poorly known at low x. Measurements of the W+c production and the inclusive W and Z differential cross sections are found to constrain the strange-quark density. Drell-Yan cross section...
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  34. Zoltan Laszlo Trocsanyi (University of Debrecen (HU))
    02/09/2015, 14:10
    Heavy Quarks
    We simulate the hadroproduction of a t tbar pair in association with one or two isolated photons at the LHC using the PowHel program. The generated events are stored according to the Les-Houches event format and constitute an almost inclusive event sample (regarding the photons), so that usual experimental photon isolation can be employed. We interface those events to the PYTHIA shower Monte...
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  35. Leszek Motyka
    02/09/2015, 14:35
  36. Klaus Rabbertz (KIT - Karlsruhe Institute of Technology (DE))
    02/09/2015, 14:40
    Recent results from CMS on jet measurements as well as jet properties and jet variables are presented together with results on alpha_s extraction and PDF constraints.
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  37. Nestor Armesto Perez (Universidade de Santiago de Compostela (ES))
    02/09/2015, 14:40
    Multi-parton Dynamics
    The Large Hadron-Electron Collider LHeC is a proposed upgrade of the LHC to study ep/eA collisions in the TeV regime, by adding a 60 GeV electron beam through an Energy Recovery Linac. In this talk we will review the possibilities for studying the small-x region in this machine, with emphasis in the potential for unravelling the existence of a novel, non-linear saturation regime of QCD through...
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  38. Katsuya Yamauchi (Nagoya University (JP))
    02/09/2015, 15:00
    Heavy Quarks
    Measurements of the inclusive top quark pair production cross sections in proton-proton collisions with the ATLAS detector at the Large Hadron Collider are presented. The most precise result requires opposite sign electrons and muons and uses the full data-set at a centre-of-mass energy of 7 and 8 TeV. In addition, differential measurements of the top transverse momentum and kinematic...
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  39. Amir Rezaeian (Universidad Tecnica Federico Santa Maria)
    02/09/2015, 15:10
    Multi-parton Dynamics
    I will discuss recent developments in calculation of prompt di-photon and photon-hadron production in proton-nucleus collisions within the Color-Glass-Condensate approach. I will discuss in details whether there is a ridge like structure in di-photon and photon-hadron correlations in high-multiplicity events in proton-proton and proton-nucleus collisions at the LHC. Such measurements at the...
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  40. Helen Brooks (IPPP/Durham University)
    02/09/2015, 15:10
  41. Mark Levy (University of Birmingham (GB))
    02/09/2015, 15:25
    Heavy Quarks
    The latest measurements of the properties of the top quark using the ATLAS experiment are presented. The top quark mass is one of the fundamental parameters of the Standard Model. A measurement based on a multi-dimensional template fit that can constrain the uncertainties on the energy measurements of jets is presented and combined with a measurement using dilepton events. In addition, novel...
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  42. Mark Sutton (University of Sussex (GB))
    02/09/2015, 15:30
    Recent developments in the fast reproduction of the results of QCD calculations using the APPLgrid project are presented. The calculation of cross-sections at Next-to-Leading order in QCD involves the integration over the final state phase space in order to cancel the infra-red divergences. For the calculation of cross sections for observables at hadron-hadron colliders this integration...
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  43. Hans Van Haevermaet (University of Antwerp (BE))
    02/09/2015, 15:40
    Experiments in the upcoming high-luminosity runs at the LHC face the challenges of very large pile-up. Primary techniques to deal with this are based on vertexing by trackers. Outside the detector tracking acceptances, however, lie regions of much interest for a great many aspects of the LHC physics program. Treatments of pile-up in these regions rely more strongly on Monte Carlo simulations....
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  44. Klaus Rabbertz (KIT - Karlsruhe Institute of Technology (DE))
    02/09/2015, 15:50
    The precise calculation of hadron-hadron collisions at higher orders of perturbative QCD requires a large amount of processing power. In addition, thorough analyses require that these calculations are repeated many times for different parameters. The fastNLO toolkit can be interfaced with next-to-leading order (NLO) and next-to-next-to-leading order (NNLO) Monte-Carlo programs to...
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  45. Steffen Rocker (KIT - Karlsruhe Institute of Technology (DE))
    02/09/2015, 15:50
    Heavy Quarks
    Measurements are presented of t-channel single top quark production in proton-proton collisions at the LHC at centre-of-mass energies of 7 and 8 !TeV, using data collected with the CMS experiment during the years 2011 and 2012. The analyses consider decay channels where the W from the top decays into electron-neutrino or muon-neutrino, and makes use of kinematic characteristics of electroweak...
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  46. Johannes Bluemlein (DESY)
    02/09/2015, 16:30
    We present the 3-loop heavy flavor non-singlet contributions to different polarized and unpolarized structure functions and associated sum-rules.
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  47. Amina Zghiche (CEA/IRFU,Centre d'etude de Saclay Gif-sur-Yvette (FR)), Amina Zghiche (LAPP-CNRS-France)
    02/09/2015, 16:30
  48. Bjoern Penning (Imperial College Sci., Tech. & Med. (GB))
    02/09/2015, 16:30
    PDFs
    We present $W$ boson and lepton charge asymmetry measurements from $W$ decays in the electron channel, with 9.7 fb$^{-1}$ of RunII data collected by the D0 detector at the Fermilab Tevatron Collider. The electron charge asymmetry is presented as a function of the electron transverse momentum and pseudo-rapidity out to $|\eta|\leq 3.2$; we also give the $W$ charge asymmetry as a function of $W$...
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  49. Hwi Dong Yoo (Seoul National University (KR))
    02/09/2015, 16:30
    Multi-parton Dynamics
    Many new physics scenarios beyond the Standard Model predict the presence of narrow or broad resonances decaying to a pair of quarks/gluons, charged/neutral leptons, photons and their combinations, or a multi-jet final state. Non-resonant excess in tails of mass and transverse momentum distributions is another strong indication of new physics. This talk highlights recent CMS searches on new...
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  50. Luminita Mihaila
    02/09/2015, 16:55
    Heavy Quarks
    In this talk, we are going to report on the recent calculation of the decay rate of the SM Higgs boson to bottom quarks at O(alpha alphas) and discuss its phenomenological implications. In the second part of the talk, we would like to point out the significance of these results in constraining the possible SM extensions.
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  51. Andrey Sapronov (Joint Inst. for Nuclear Research (RU))
    02/09/2015, 17:00
    PDFs
    The uncertainties of protons parton distribution functions (PDFs) play a dominant role for the precision tests of the Standard Model (SM) and they also impact substantially the theory predictions of Beyond SM high mass production. We present the HERAFitter project which provides a unique open-source software framework for the determination of the proton's PDFs and for the interpretation of...
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  52. Bo Liu (Academia Sinica (TW)/Shandong University(CN)), Bo Liu, Bo.Bo Liu (Tsinghua University (CN))
    02/09/2015, 17:00
  53. Alison Elliot (University of Victoria (CA))
    02/09/2015, 17:00
    Multi-parton Dynamics
  54. Rhorry Graham Gauld
    02/09/2015, 17:20
    Heavy Quarks
    Last year, LHCb performed the first measurement of the angular asymmetry present in bottom-quark pair production at a hadron collider. I will compare the available data to SM predictions, and comment on the potential sensitivity of similar measurements in Run-II. In addition, I will also discuss the feasibility of charm- and top-quark pair asymmetry measurements with Run-II data.
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  55. Walter Giele
    02/09/2015, 17:30
    Hard QCD
    The calculation and phenomenology of PP->H+1 jet and PP->V+1 jet at NNLO will be presented. The calculations use the so-called jettiness subtraction which makes it easy to combine the 2-loop virtual corrections into MCFM by using the already build-in NLO PP->H+2 parton and PP->V+2 parton processes.
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  56. Nestor Armesto Perez (Universidade de Santiago de Compostela (ES))
    02/09/2015, 17:30
    PDFs
    The Large Hadron-Electron Collider LHeC is a proposed upgrade of the LHC to study ep/eA collisions in the TeV regime, by adding a 60 GeV electron beam through an Energy Recovery Linac. In this talk new results are presented on the physics prospects on energy frontier eA collisions with this machine, with emphasis new results on the precise determination of nuclear parton densities.
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  57. Mr Christoph Borschensky (WWU Münster)
    02/09/2015, 17:30
    Multi-parton Dynamics
    In light of the recent upgrade of the Large Hadron Collider (LHC), precise calculations for the production of supersymmetric particles are required to test new physics models. The all-order resummation of soft and Coulomb gluons deals with potentially large terms endangering the perturbative series and can enhance the production cross sections in certain kinematical regions. In this talk,...
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  58. Fabrizio Margaroli (Universita e INFN, Roma I (IT))
    02/09/2015, 17:45
    Heavy Quarks
    This talk presents searches for new phenomena in signatures with a pair of top-quarks, a top and bottomquark, together with searches for fermionic top/bottom partners (VLQs). CMS results from Run-1 and Run-2 (if available) will be presented together with their interpretations, with a view to the reconstruction techniques used in the searches.
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  59. Markus Christian Schulze (CERN)
    02/09/2015, 17:50
    I will present new results for the fully differential Higgs plus jet cross section at NNLO in perturbative QCD which include decays of the Higgs boson to electroweak vector bosons. I will review some technical details of the computation, present kinematic distributions for a realistic final state, and compare our findings with the experimental measurements.
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  60. Teppei Katori (Queen Mary University of London)
    02/09/2015, 18:00
    Multi-parton Dynamics
    Next generation neutrino oscillation experiments utilize details of hadronic final states to improve the precision of neutrino interaction measurements. The hadronic system was often neglected or poorly modelled in the past, but they have significant effects on high precision neutrino oscillation and cross-section measurements. Among the physics of hadronic systems in neutrino...
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  61. Claire Gwenlan (University of Oxford (GB))
    02/09/2015, 18:00
    PDFs
    The LHeC is a proposed upgrade of the LHC to study ep/eA collisions in the TeV regime, by adding a 60 GeV electron beam through an Energy Recovery Linac. New evaluations are presented on the prospects for precisely determining the proton PDFs, with complete flavour unfolding in a single experiment, and the strong coupling constant with per mille accuracy.
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  62. Marco Bonvini (University of Oxford)
    02/09/2015, 18:10
    Hard QCD
    I will describe how approximate higher order results can be obtained from known asymptotic regimes, in turn determined by all-order resummed expressions. Specifically, threshold (large-x) resummation combined with high-energy (small-x) resummation can lead to reliable determinations of inclusive N3LO cross sections such as those of Higgs, $t\bar t$ or Drell-Yan productions. The method is...
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  63. Sebastian Pedraza Lopez (Instituto de Fisica Corpuscular (ES))
    02/09/2015, 18:10
    Heavy Quarks
    Measurements of single top-quark production in proton proton collisions at 7 and 8 TeV are presented. In the leading order process, a W boson is exchanged in the t-channel. The single top-quark and anti-top total production cross sections, their ratio, as well as a measurement of the inclusive production cross section is presented. In addition, a measurement of the production cross section of...
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  64. Dr Alexander Hasselhuhn (Karlsruhe Institute of Technology)
    02/09/2015, 18:30
    Hard QCD
    The total production cross section from gluon fusion is an important ingredient in further studies of the discovered Higgs boson. I will present the analytic computation of the NNNLO QCD corrections to its total production cross section in the qq'-channel. The computation is performed using differential equations for canonical bases of master integrals, and the results are exact in the Higgs...
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  65. Abilio De Freitas (DESY - Zeuthen)
    03/09/2015, 09:00
  66. Matthew David Needham (University of Edinburgh (GB))
    03/09/2015, 09:40
  67. Javier Cuevas Maestro (Universidad de Oviedo)
    03/09/2015, 10:20
  68. Zoltan Laszlo Trocsanyi (University of Debrecen (HU))
    03/09/2015, 11:30
    Hard QCD
    We compute the fully differential decay rate of the standard model Higgs boson to a b-quark pair at NNLO accuracy. We use a general subtraction scheme developed for computing QCD jet cross sections in perturbation theory. The double real and real-virtual contributions to the second order radiative corrections, regularized by subtractions, are finite in four space-time dimensions and their...
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  69. Lucia Grillo (Ruprecht-Karls-Universitaet Heidelberg (DE))
    03/09/2015, 11:30
  70. Luca Rottoli
    03/09/2015, 11:30
    PDFs
    I will present NNPDF3.0, the first set of parton distribution functions (PDFs) determined with a methodology validated by a closure test. NNPDF3.0 uses a global dataset including HERA-II deep-inelastic inclusive cross-sections, the combined HERA charm data, jet production from ATLAS and CMS, vector boson rapidity and transverse momentum distributions from ATLAS, CMS and LHCb, W+c data from CMS...
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  71. Frederic Alexandre Dreyer (LPTHE & CERN)
    03/09/2015, 11:50
    Hard QCD
    In this talk, we will present the fully differential NNLO corrections to vector-boson fusion (VBF) Higgs production at hadron colliders, in the limit in which there is no cross-talk between the hadronic systems associated with the two protons. This result is achieved by combining an inclusive NNLO calculation in the structure-function approach and a suitably factorised NLO VBF Higgs plus 3-jet...
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  72. Harry Victor Cliff (University of Cambridge (GB))
    03/09/2015, 11:55
  73. Juan Rojo Chacon (University of Oxford (GB))
    03/09/2015, 12:00
    PDFs
    The current PDF4LHC recommendation to estimate uncertainties due to parton distribution functions (PDFs) in theoretical predictions for LHC processes involves the combination of separate predictions computed using PDF sets from different groups, each of which comprises a relatively large number of either Hessian eigenvectors or Monte Carlo (MC) replicas. While many fixed-order and parton...
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  74. Nicolas Greiner (DESY)
    03/09/2015, 12:10
    Hard QCD
    The largest contribution of the production of a Standard Model Higgs comes from the gluon fusion mechanism. The production of a Higgs in association with jets in this production mode is an important and dominant background to the VBF case. Its precise understanding is therefore mandatory for the reliable determination of the Higgs couplings and its properties. In this talk we present a...
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  75. Marco Pappagallo (University of Glasgow (GB))
    03/09/2015, 12:20
  76. Huasheng Shao (CERN)
    03/09/2015, 12:30
    Hard QCD
    I will first review the status of the perturbative computations with QCD and electroweak corrections in the MadGraph5_aMC@NLO framework. Then, I will focus on its first phenomenological application to top quark pair associated production with a Higgs/Z/W boson at next-to-leading order QCD and electroweak accuracy. As a by product, I also present some preliminary results for the top quark pair...
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  77. Albert De Roeck (CERN)
    03/09/2015, 12:30
    PDFs
    In 2010 the PDF discussion forum PDF4LHC provided a recommendation for parton distributions and uncertainties based on existing PDF sets from different PDF fitting groups. These recommendations have been widely used, notably in the LHC Higgs study groups, and for experimental result systematics by the experiments. PDF4LHC has worked over the past few years to re-evalute the procedures and...
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  78. Wouter Waalewijn (Nikhef / UvA)
    04/09/2015, 09:00
  79. Andreas von Manteuffel (University of Zürich)
    04/09/2015, 09:40
  80. Chiara Ilaria Rovelli (Universita e INFN, Roma I (IT))
    04/09/2015, 10:20
  81. Minjung Kim (Inha University (KR))
    04/09/2015, 11:30
    Heavy Quarks
    Heavy quarks (charm and beauty) are essential probes of the evolution of the medium created in heavy-ion collisions, because heavy-quark production in high-energy collisions occurs early compared to the formation time of the strongly-interacting partonic matter. To quantify medium effects in AA collisions, one needs to study pp collisions and p-A collisions as references. The measurements of...
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  82. Wally Melnitchouk (Jefferson Lab)
    04/09/2015, 11:30
    PDFs
    We present the results of a new global QCD analysis of PDFs from the CTEQ-Jefferson Lab collaboration (dubbed "CJ15"), which includes several new data sets and recent theoretical developments. In particular, we study the constraints from new D0 data on *W* boson asymmetries on the *d/u* PDF ratio at large *x*, and, indirectly, on the models of nuclear corrections in the deuteron. The analysis...
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  83. Benjamin Tannenwald (University of Kansas), Benjamin Tannenwald (Ohio State University (US))
    04/09/2015, 11:30
    Hard QCD
    The inclusive production of W and Z bosons as well the off­-shell Z/gamma* production are standard candles at hadron colliders. The measurement of their production cross­-sections can be compared to theory calculations at NNLO QCD and have an impact on our knowledge of the parton densities of the proton. Run­1 studies carried out by the ATLAS Collaboration are reviewed and first LHC Run­2...
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  84. Fabrizio Margaroli (Universita e INFN, Roma I (IT))
    04/09/2015, 11:55
    Heavy Quarks
    In this talk searches for Higgs bosons produced in association with top quarks are presented. The searches are performed using the data collected during the first LHC run at a center-of-mass energy of 7 and 8 TeV and results are presented for different Higgs decay final states, including bbbar, tautau, WW*/ZZ* and gg, as well as their combination. The talk highlights experimental and...
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  85. Jonas Lindert
    04/09/2015, 12:00
    Hard QCD
    Run-II of the LHC is probing the Standard Model of particle physics at unprecedented energies and precision. At such large energy scales higher-order electroweak (EW) corrections are strongly enhanced due to the presence of large Sudakov logarithms. Their inclusion in the experimental analyses will significantly enhance the sensitivity for new phenomena. In my talk I will present a fully...
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  86. Amanda Sarkar (University of Oxford (GB))
    04/09/2015, 12:00
    PDFs
    The impact of recent measurements of heavy-flavour production in deep inelastic $ep$ scattering and in $pp$ collisions on parton distribution functions is studied in a QCD analysis in the fixed-flavour number scheme at next-to-leading order. Differential cross sections of charm- and beauty-hadron production measured by LHCb are used together with inclusive and heavy-flavour production cross...
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  87. Darren Price (University of Manchester (GB))
    04/09/2015, 12:20
    Heavy Quarks
    The production of heavy flavour jets in association with a vector boson is a process of some importance for searches for new phenomena and precision studies of QCD, which has nonetheless proven difficult to extract and measure in detail. A large and precisely-understood dataset from $p\bar{p}$ collisions at the Tevatron, and the development of techniques at the DZero experiment to isolate the...
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  88. Thomas Morgan (IPPP Durham University)
    04/09/2015, 12:20
    We will review our recent calculation of Z boson production in association with a jet up to Next-to-Next-to Leading Order (NNLO) precision in QCD, as shown in arXiv:1507.02850. This is a key process at the LHC, given its large event rate and clean signature with the Z boson decaying leptonically. We will discuss our approach using the antenna subtraction scheme and present new results of the...
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  89. Rhorry Gauld (IPPP Durham University)
    04/09/2015, 12:30
    PDFs
    Measurements of forward heavy quark production simultaneously provides sensitivity to relatively large- and small-$x$ PDFs. I will discuss how measurements of prompt charm production (with carefully selected observables) can be used to constrain the gluon PDF for values of $x < 10^{-5}$ --- a kinematic region which is not well constrained by pre-LHC data.
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  90. German Sborlini (IFIC-Valencia)
    04/09/2015, 12:40
    Higher-order computations require to combine real and virtual contributions in order to cancel infrared (IR) singularities. Loop-tree duality (LTD) allows to express virtual contributions in terms of phase-space integrals, which enables to add them directly to the real radiation terms. Thus, we obtain expressions that can be integrated in four dimensions and we avoid the introduction of IR...
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  91. Tai-Hua Lin (Johannes-Gutenberg-Universitaet Mainz (DE))
    04/09/2015, 14:00
    The ATLAS Collaboration has performed precision measurements of the transverse momentum of Z/gamma* bosons and their decay lepton angular decorrelation with the phi* observable. Measurements have been performed at 7 and 8 TeV in different di­lepton invariant mass and rapidity regions. These measurements are sensitive to soft resummation effects and hard jet emissions for small and large...
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  92. Jay Lawhorn (California Institute of Technology (US))
    04/09/2015, 14:30
    The production of W and Z bosons is studied in pp collisions at a center-of-mass energy of 8 TeV using data collected in the CMS experiment. W events are selected containing an isolated, energetic electron or muon. Z events are selected containing a pair of isolated, energetic electrons or muons. Data-driven methods are used to estimate reconstruction and triggering efficiencies, and well as...
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  93. Marco Bonvini (University of Oxford)
    04/09/2015, 15:00
    I will discuss the inclusion of an intrinsic component of the Charm PDF to the FONLL variable flavour number scheme, and the implications for a PDF fit.
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  94. Keith Hamilton (UCL)
    04/09/2015, 15:00
    Hard QCD
    I will discuss the matching of next-to-next-to-leading order QCD corrections with parton shower simulations for simple processes, via extension of the multi-scale improved NLO (MiNLO) framework.
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  95. Ye Li (SLAC)
    04/09/2015, 15:30
    Hard QCD
    We discuss recent developments in combining parton showers and fixed-order calculations. We focus on the UNNLOPS method for matching next-to-next-to-leading order computations to the parton shower, and we present results from Sherpa for Drell-Yan lepton-pair and Higgs-boson production at the LHC.
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  96. Ronan James Wallace (University College Dublin (IE))
    04/09/2015, 15:30
    LHCb's unique forward acceptance allow for complementary measurements of production processes of electroweak bosons and quarkonia at large rapidities and low transverse momenta. A review of the latest results based on run 1 data will be presented.
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  97. Alexander Law (University of California,Santa Cruz (US))
    04/09/2015, 16:30
    The production of heavy flavour in association with a W or Z boson represent important backgrounds to Higgs and BSM studies and are challenging to calculate in QCD. Several precision measurements were performed using pp data at 7 TeV of integrated as well as differential cross sections. Comparisons are made to a diverse set of state-­of­the­-art NLO QCD calculations, some of which are...
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  98. Alessandra Baas (Ruprecht-Karls-Universitaet Heidelberg (DE))
    04/09/2015, 16:30
    Hard QCD
    ATLAS measurements of multi­-boson production processes involving combinations of W, Z and isolated photons are summarized. In processes like WW, ZZ, Zgamma or Wgamma large next­-to­-next­-to­-leading order QCD corrections were recently calculated and are confronted with integrated and differential data measurements. Furthermore a measurement of the differential cross section for the...
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  99. Massimiliano Grazzini (Universitaet Zuerich (CH))
    04/09/2015, 17:00
    Hard QCD
    We consider QCD radiative corrections to vector boson pair production in hadron collisions. We report on the computation of radiative corrections to NNLO in QCD perturbation theory. We present results for Zgamma, Wgamma and ZZ production at the LHC by using the selection cuts typically applied by the LHC experiments. Our calculation consistently includes the leptonic decay of the vector-bosons...
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  100. Jelena Luetic (Institute Rudjer Boskovic (HR))
    04/09/2015, 17:00
    Accurate modeling of V+jets is important for many measurements at the LHC. W/Z+jets is for example a dominant background for precision top quark measurements. After the discovery of the Higgs boson and the beginning of the Higgs precision measurement era, accurate modeling of the background processes is essential. Many searches for physics beyond standard model also rely on precise SM...
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  101. Lorena Rothen (University of Bern)
    04/09/2015, 17:30
    Hard QCD
    In electroweak-boson production processes with a jet veto, higher-order corrections are enhanced by logarithms of the veto scale over the invariant mass of the boson system. We resum these Sudakov logarithms at next-to-next-to-leading logarithmic (NNLL) accuracy and match our predictions to next-to-leading order (NLO) fixed-order results. The calculation is performed in an automated way, for...
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  102. Philip Ilten (Massachusetts Inst. of Technology (US))
    04/09/2015, 17:30
    LHCb has a unique capability to separate beauty and charm jets. We present recent results on jet tagging performance, W+b,c jets and the observation of the top quark in the forward acceptance at the LHC.
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  103. Davison Soper (University of Oregon)
    05/09/2015, 09:00
  104. Frank Siegert (Technische Universitaet Dresden (DE))
    05/09/2015, 09:40
  105. Andreas Morsch (CERN)
    05/09/2015, 10:20
  106. Thomas Gehrmann (University of Zurich)
    05/09/2015, 11:30
  107. Hannes Jung (Deutsches Elektronen-Synchrotron Hamburg and Zeuthen (DE))
    05/09/2015, 12:20
  108. Eram Syed Rizvi (Queen Mary, University of London)
    05/09/2015, 13:10
  109. Johannes Bluemlein (DESY)
    Heavy Quarks
    We present the 3-loop heavy flavor non-singlet contributions to different polarized and unpolarized structure functions and associated sum-rules.
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  110. Multi-parton Dynamics
    The differential diffractive cross section is measured as a function of xi= M_X^2/s in the region dominated by single dissociation (SD) and double dissociation (DD), where M_X is the mass of one of the two final-state hadronic systems separated by the largest rapidity gap in the event. The cross section is also measured as a function of the width of the central rapidity gap in the region...
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  111. Hard QCD
    A search for exclusive or quasi-exclusive W+W- production induced by photon-photon exchange in pp collisions at sqrt(s)=8 TeV is reported using data corresponding to an integrated luminosity of 19.7/fb. Events are selected by requiring the presence of an electron-muon pair with large transverse momentum pT > 30 GeV and no associated charged particles detected from the same vertex. The observed...
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  112. Hard QCD
    The measurements of the Higgs boson properties, mass, spin/CP, couplings, off-shell cross sections and constraints on invisible width, as well as other Standard model measurements at CMS will be presented. The analysis is based on pp collision data collected at centre-­of-­mass energies of 7 and 8 TeV by the CMS experiment at the LHC, corresponding to integrated luminosities of 5/fb and 20/fb,...
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  113. Hard QCD
    This talk will present in detail the analysis by CMS on the Higgs fiducial and differential cross sections
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  114. German Sborlini (IFIC-Valencia)
    Hard QCD
    Higher-order computations require to combine real and virtual contributions in order to cancel infrared (IR) singularities. Loop-tree duality (LTD) allows to express virtual contributions in terms of phase-space integrals, which enables to add them directly to the real radiation terms. Thus, we obtain expressions that can be integrated in four dimensions and we avoid the introduction of IR...
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  115. Multi-parton Dynamics
    A measurement of the underlying event activity in pp collisions is performed using events with a leading charged particle jet produced at central pseudorapidities and of transverse momentum in the range of 1 to 100 GeV. The underlying event activity is measured independently in the two halves of the transverse region with the maximum as well as minimum activities. The results obtained from pp...
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  116. Leszek Motyka
    Multi-parton Dynamics
    A report will be given on work in progress on the calculation of the soft gluon corrections to the Higgs boson production at the LHC in association with t-tbar pair. Preliminary results will be presented for the inclusive cross-section including the resummed soft gluon corrections at the NLL accuracy matched to the known NLO QCD results. The estimates of theoretical uncertainty of the NLL+NLO...
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  117. Wouter Waalewijn (Nikhef / UvA)
    Hard QCD
    Many LHC analyses involve cuts on several observables, but resummed predictions are mostly restricted to single variables. We show how the simultaneous resummation of multiple observables can be achieved through the construction of novel effective field theories, increasing the precision of theoretical predictions. I will discuss two different prototypical examples: (1) Jet substructure: the...
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  118. Multi-parton Dynamics
    The CMS Collaboration has a comprehensive program of small-x QCD and forward physics measurements, which is supported by an excellent experimental coverage into the very forward phase space. Some of the highlights in terms of testing QCD at low-pt and at high pseudorapidities with jets and charged particles are summarized. Also extremely rare processes, as the measurement of exclusive W-pair...
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  119. Hard QCD
    Several aspects of jet production in pp collisions have been measured by the ATLAS collaboration. The momentum-weighted sum of the charges of tracks associated to a jet is sensitive to the electrical charge of the parton initiating the jet. The distribution of the so­-called jet charge has been measured in dijet events using pp collision data at 8 TeV with the ATLAS detector. The measurement...
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  120. Multi-parton Dynamics
    Several measurements of jet final states are presented performed at different center-of-mass energies and down to very low pt. The simultaneous observation of several jets in the same event is exploited to study for example the angular correlations of Mueller Navelet jet topologies in order to search for the signature of BFKL parton dynamics. But multi-jet measurements are also used to test...
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  121. Helen Brooks (IPPP/Durham University)
    Hard QCD
    High Energy Jets calculates the leading corrections to partonic processes with at least two jets and in the Multi-Regge-Kinematic limit of large invariant masses between all partons compared to the individual transverse momenta. An all-order calculation is constructed by explicitly combining the leading virtual and real corrections. This leads to a superior description in the relevant region...
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  122. Helen Brooks (IPPP/Durham University)
    High Energy Jets calculates the leading corrections to partonic processes with at least two jets and in the Multi-Regge-Kinematic limit of large invariant masses between all partons compared to the individual transverse momenta. An all-order calculation is constructed by explicitly combining the leading virtual and real corrections. This leads to a superior description in the relevant region...
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