Ilse Kratschmer
(Austrian Academy of Sciences (AT))
7/23/15, 9:00 AM
QCD and Hadronic Physics
talk
This talk presents the CMS quarkonium production results in pp collisions, placing emphasis on the most recent measurements, which include the S-wave Psi(nS) and Y(nS) cross sections up to transverse momenta exceeding 100 GeV with the Run-1 dataset, and reports on the prospects for B physics measurements with high statistics data at CMS, and presents preliminary results obtained with 13 TeV data.
Stefanos Leontsinis
(National Technical Univ. of Athens (GR))
7/23/15, 9:15 AM
QCD and Hadronic Physics
talk
We present a large number of detailed measurements of the production of various open and hidden charm (D meson, J/psi, psi(2s), chi_c) states at the ATLAS experiment at centre- of-mass energies of 2.76 TeV, 7 TeV, and 8 TeV. The total charm production cross-section at the LHC is also determined. These measurements extend in reach and precision beyond those currently available, and we compare...
Barbara Trzeciak
(Czech Technical University in Prague)
7/23/15, 9:30 AM
QCD and Hadronic Physics
talk
Despite extensive studies, the J/$\psi$ production mechanism in hadron collisions is not yet exactly known.
For many years, mostly J/$\psi$ differential cross-section measurements have been used to test different J/$\psi$ production models. While many models can reasonably well describe the experimental data on the J/$\psi$ cross-section in $p+p$ collisions, they have different predictions...
Alexei Garmash
(Princeton)
7/23/15, 9:45 AM
QCD and Hadronic Physics
talk
Recent observations of charged charmonium-like states have opened an interesting landscape in the field of hadron spectroscopy. Continuing with its tradition, Belle recently observed a new charged charmonium-like state Zc(4200) and obtained an evidence for Zc(4430) → J/ψπ+ in B → J/ψπK decays. Belle also found the first evidence for a new charged state Zc(4020)+ in their updated study of ISR...
Yutie Liang
(Giessen University)
7/23/15, 10:00 AM
QCD and Hadronic Physics
talk
The BESIII Experiment at the Beijing Electron Positron Collider (BEPCII) has accumulated the world's largest samples of $e^+e^-$ collisions in the tau-charm region. From the collected samples, which include $e^+e^-$ annihilations at J/psi, psi(2S), psi(3770) peaks and in the region from 4 GeV to 4.6 GeV, BESIII has produced many new results in the spectroscopy, transitions, and decays of...
Sheldon Stone
(Syracuse University (US))
7/23/15, 10:15 AM
QCD and Hadronic Physics
talk
Observations of exotic structures in the $J/\psi p$ channel, that we refer to as pentaquark-charmonium states, in $\Lambda_b^0 \to J/\psi p K^-$ decays are presented. The data sample corresponds to an integrated luminosity of $3~fb^{-1}$ acquired with the LHCb detector from 7 and 8~TeV $pp$ collisions. An amplitude analysis is performed on the three-body final state that reproduces all the...
James William Walder
(Lancaster University (GB))
7/23/15, 10:30 AM
QCD and Hadronic Physics
talk
Hadronic spectroscopy has experienced a renaissance in the last decade thanks to experiments at B-factories and Tevatron and recently at the LHC. A wide zoology of quarkonium-like states still needs to be understood within a possibly consistent framework that the LHC experiments are now contributing to enrich. The latest results on the production and decay properties of exotic mesons in the...
7/23/15, 10:45 AM
QCD and Hadronic Physics
talk
We present a measurement of the production cross section of the D+ mesons in proton-antiproton collisions at 1.96 TeV center-of-mass energy, using the full data set collected by the CDF experiment at the Tevatron collider during Run II. The measurement is performed in a yet unexplored low transverse momentum range, down to 1.5 GeV/c, using events collected with the "zero bias" and "minimum...
Darren Price
(University of Manchester (GB))
7/23/15, 11:30 AM
QCD and Hadronic Physics
talk
We present recent results on heavy flavor jet production in association with weak vector bosons using proton-antiproton collision data collected with the D0 detector at center of mass energy of 1.96 TeV. Studies of these processes provide tests of perturbative QCD predictions and non-perturbative effects. They are also important backgrounds to many precision SM measurements as well as searches...
Ivan Polyakov
(ITEP Institute for Theoretical and Experimental Physics (RU))
7/23/15, 11:45 AM
QCD and Hadronic Physics
talk
Its forward acceptance puts the LHCb in a unique position at the LHC to measure QCD phenomena at large rapidities and low transverse momenta, where theoretical models often fail to describe the data accurately. We present new studies of the production of the ϒ meson of the Λb baryon.
Grazia Luparello
(Universita e INFN, Trieste (IT))
7/23/15, 12:00 PM
QCD and Hadronic Physics
talk
Heavy quarks, i.e. charm and beauty, are produced in hard parton scatterings in the initial stages of hadronic collisions. The study of their production in pp collisions at LHC energies provides, therefore, a test of perturbative QCD calculations at the highest collision energies available.
In addition to the heavy-flavour production cross sections, more differential measurements provide...
Iain Bertram
(Lancaster University)
7/23/15, 12:15 PM
QCD and Hadronic Physics
talk
We present a first study of the inclusive production of the X(4140) state in hadronic collisions. We report the X(4140) production rate and a new measurement of its mass and width. The results of searches for the Zb(10610) and the Zb(10650) using the decay Zb → Υ(nS)π± where Upsilon(nS) → μμ are also presented. Sensitivity to the production of Zb is demonstrated.
We present a measurement of...
Paolo Gandini
(University of Oxford (GB))
7/23/15, 12:30 PM
QCD and Hadronic Physics
talk
Its forward acceptance puts the LHCb in a unique position at the LHC to measure QCD phenomena at large rapidities and low transverse momenta, where theoretical models often fail to describe the data accurately. We present new exclusive production studies of ϒ mesons. A first look at the new Run II data and the performance of the new HERSCHEL forward counters may be presented.
Alexey Guskov
(Joint Inst. for Nuclear Research (RU))
7/23/15, 12:45 PM
QCD and Hadronic Physics
talk
The electric (${\alpha}_{\pi}$) and the magnetic (${\beta}_{\pi}$) polarisabilities are fundamental properties of the pion characterising the rigidity of its internal structure as a complex QCD system. They have been precisely measured at the
COMPASS experiment at CERN with a ${\pi}^{-}$ beam of 190~GeV/c
assuming ${\alpha}_{\pi}+{\beta}_{\pi}=0$. Muons of the same
momentum were used for...
Jesper Roy Christiansen
(Lund University (SE))
7/23/15, 2:30 PM
QCD and Hadronic Physics
talk
Recent progress on colour reconnection within the PYTHIA framework
is presented. A new model is introduced, based on the SU(3) structure
of QCD and a minimization of the potential string energy. The
inclusion of the epsilon structure of SU(3) gives a new baryon
production mechanism and makes it possible simultaneously to describe
hyperon production at both ee and pp colliders....
Nadine Fischer
(KIT - Karlsruhe Institute of Technology (DE)),
Peter Skands
(Monash University (AU)),
Simon Plaetzer
(ITP, Universitaet Karlsruhe),
Stefan Gieseke,
Stefan Kluth
(Max-Planck-Institut fuer Physik (Werner-Heisenberg-Institut) (D)
7/23/15, 2:45 PM
QCD and Hadronic Physics
talk
A study of QCD coherence is presented based on a sample of about
397.000 e$^+$e$^-$ hadronic annihilation events collected at
$\sqrt{s}=91$ GeV with the OPAL detector at LEP. The study is based
on four recently proposed observables that are sensitive to coherence
effects in the perturbative regime. The measurement of these
observables is presented, along with a comparison with the...
Thorsten Kuhl
(Deutsches Elektronen-Synchrotron Campus Zeuthen (DE))
7/23/15, 3:00 PM
QCD and Hadronic Physics
talk
The ATLAS collaboration has carried out several measurements of
particle production properties and correlations at different pp collisions
centre-of-mass energies.
The production properties of mesons and baryons at sqrt(s)=7 TeV are presented
and compared to predictions. The effects of space-time geometry in the
hadronization phase has been studied in the context of...
Anthony Morley
(University of Sydney (AU))
7/23/15, 3:30 PM
QCD and Hadronic Physics
talk
Measurements are presented from proton-proton collisions at different centre-of-mass energies in the range of 0.9 to 13 TeV recorded with the ATLAS detector at the LHC. The charged-particle multiplicity, its dependence on transverse momentum and pseudorapidity, and the relationship between the mean transverse momentum and charged-particle multiplicity are measured. The results are corrected...
Hans Van Haevermaet
(University of Antwerp (BE))
7/23/15, 3:45 PM
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...
Antoni Szczurek
(Institute of Nuclear Physics),
Rafal Maciula
(Institute of Nuclear Physics PAN)
7/23/15, 4:30 PM
QCD and Hadronic Physics
talk
We present first results for the $2 \to 4$ single-parton scattering
$g g \to c \bar c c \bar c$ subprocess for the first time fully within
the $k_t$-factorization approach. In this calculation we have used
the Kimber-Martin-Ryskin unintegrated gluon distribution which effectively
includes some class of higher-order gluon emissions, and an off-shell
matrix element squared calculated using...
Marko Bracko
(Jozef Stefan Institute)
7/23/15, 4:45 PM
QCD and Hadronic Physics
talk
The $e^+ e^−$ annihilation process provides an access to the fragmentation functions due to its clean environment. Using the high-statistics dataset accumulated by the Belle detector at the KEKB asymmetric-energy $e^+ e^−$ collider, we report the first measurements of the double differential cross section of identified di-hadrons (pions and kaons) with respect to the two hadron's fractional...
Per Grafstrom
(Universita e INFN, Bologna (IT))
7/23/15, 5:00 PM
QCD and Hadronic Physics
talk
The total pp cross section is a fundamental parameter of the strong interaction which cannot be calculated in QCD but still can be measured using the optical theorem, which states that the total cross section can be obtained from the extrapolation to t=0 of the differential elastic cross section measured at small four-momentum transfer t.
The ATLAS Collaboration has collected 80 mub-1 of...
Hans Van Haevermaet
(University of Antwerp (BE))
7/23/15, 5:15 PM
QCD and Hadronic Physics
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...
Ankita Mehta
(Panjab University (IN))
7/23/15, 5:45 PM
QCD and Hadronic Physics
talk
Double parton scattering is measured in different channels using the CMS experiment at the CERN LHC. Data from pp collisions collected at 7 and 8 TeV center-of-mass energy are used. Several final states are investigated to identify and measure the signature of double parton scattering in inelastic events. Parameters are extracted from the data that are suited in an optimal way to distinguish...
Jan Hladky
(Acad. of Sciences of the Czech Rep. (CZ))
7/24/15, 9:15 AM
H1 and ZEUS have published single-differential cross sections for
inclusive $D^{\star}$ meson production in deep-inelastic ep scattering at HERA
from their respective final data sets. These cross sections are
combined in the common visible phase space region of photon virtuality
$Q^2> $5 GeV², electron inelasticity $0.02 < y< 0.7$ and the $D^{\star}$ meson's transverse momentum...
Panos Kokkas
(University of Ioannina (GR))
7/24/15, 9:30 AM
Recent results on PDF constraints from CMS are presented.
Kristin Lohwasser
(Deutsches Elektronen-Synchrotron Campus Zeuthen (DE))
7/24/15, 9:45 AM
Improved determination of the strange sea distribution in the nucleon is presented. Recent charm production data in neutrino-nucleon deep-inelastic scattering by the NOMAD and CHORUS experiments and from charged current inclusive deep-inelastic scattering at HERA are used. The results are consistent with the data from the ATLAS and the CMS experiments on the associated production of...
Eva-Maria Kabuss
(Johannes Gutenberg-Universitat)
7/24/15, 10:00 AM
The COMPASS experiment at CERN performs a rich program in inclusive (DIS) and
semi-inclusive (SIDIS) deep inelastic scattering of longitudinally polarised
muons off longitudinally polarised nucleons. The main topic is the
investigation of the spin structure of the nucleon in terms
of quark and gluon polarisations. For the extraction of the contribution
of the different quarks flavours...
Katerina Lipka
(Deutsches Elektronen-Synchrotron (DE))
7/24/15, 10:15 AM
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...
Achim Geiser
(Deutsches Elektronen-Synchrotron Hamburg and Zeuthen (DE))
7/24/15, 10:30 AM
The combined HERA data on charm production in deep inelastic scattering have recently
been used to determine the charm quark running mass $m_c(m_c)$ in the $\overline{MS}$ renormalisation
scheme. The same data are used differentially as a function of the photon virtuality
Q² to evaluate the charm quark running mass at different scales to one-loop order. The scale
dependence of the mass is...
Johannes Bluemlein
(DESY)
7/24/15, 10:45 AM
A survey is presented on the calculation of the 3-loop QCD corrections to the heavy flavor Wilson coefficients in deep-inelastic scattering in the region of large momentum transfer $Q^2 \gg m^2$ and on the 3-loop matching coefficients in the variable flavor number scheme. Results are presented for the flavor non-singlet and pure singlet cases and for contributions due to Feynman diagrams...
Robert Samuel Thorne
(University College London (UK))
7/24/15, 11:30 AM
We present the MMHT2014 PDFs, an update of the previous major release in the same framework, i.e. MSTW2008. 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...
Voica Ana Maria Radescu
(Ruprecht-Karls-Universitaet Heidelberg (DE))
7/24/15, 11:45 AM
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...
Voica Ana Maria Radescu
(Ruprecht-Karls-Universitaet Heidelberg (DE))
7/24/15, 12:00 PM
The new combined inclusive HERA cross sections were input to QCD
analyses at NNLO, NLO and LO providing a new set of parton
distribution functions, HERAPDF2.0. Besides the small experimental
uncertainties, model and parameterisation uncertainties were also
considered. The consistency of data and the QCD fit was tested for
variants of the fit such as the treatment of heavy flavour...
Ali Khorramian
(IPM and Semnan University)
7/24/15, 12:15 PM
We present a comparative analysis of the non-perturbative intrinsic
charm quark contribution in the proton, using the inclusive production
of $\gamma +c $-jet in $ pp $ and $ p\bar{p} $ collisions and for the
kinematic regions that are sensitive to this contribution. We discuss
the $ Q^2 $ evolution of intrinsic quark distributions and present a code that provide these distributions as...
Katarzyna Wichmann
(Deutsches Elektronen-Synchrotron Hamburg and Zeuthen (DE))
7/24/15, 12:30 PM
An extendend QCD analysis of the new combined inclusive HERA was
performed at NLO, also including HERA data on jet and charm production.
This enables the simultaneous measurement of parton distribution
functions and the strong coupling using data from HERA alone. The strong
coupling is measured to be $\alpha_s(M_Z)$= 0.1182 ±0.0008(exp) ±0.0005(model/param.) ±0.0012(hadronisation)...
Juan Rojo Chacon
(University of Oxford (GB))
7/24/15, 12:45 PM
I 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...
Alexander Karlberg
(University of Oxford (GB))
7/24/15, 2:30 PM
QCD and Hadronic Physics
talk
I will present 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.The result is obtained by combining an inclusive NNLO
calculation in the structure-function approach and a suitably factorised
NLO VBF Higgs plus 3-jet...
Ilya Komarov
(Ecole Polytechnique Federale de Lausanne (CH))
7/24/15, 2:45 PM
QCD and Hadronic Physics
talk
The very first Run II LHC data allows LHCb to measure the cross-sections for quarkonia, beauty and charm productions. Results should be available quickly thanks to the new "Turbo" stream procedure allowing the analysis of particle candidates selected at trigger level without the need of offline reconstruction. First results are presented, conditional on LHC machine operation.
Manfred Kraus
(RWTH Aachen)
7/24/15, 3:00 PM
QCD and Hadronic Physics
talk
We give a short review of the shower concept, first introduced by Nagy and Soper, that includes full quantum correlations in the shower evolution. We also state the current status of implementation of the
publicly available shower program Deductor. However, the main focus of the talk will be the matching of the shower at next-to-leading order within the MC@NLO formalism. Matching is necessary...
Zoltan Laszlo Trocsanyi
(University of Debrecen (HU))
7/24/15, 3:15 PM
QCD and Hadronic Physics
talk
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...
Sebastian Buchta
(IFIC Valencia)
7/24/15, 3:30 PM
QCD and Hadronic Physics
talk
The Loop-Tree Duality (LTD) is a novel perturbative method in QFT that establishes a relation between loop–level and tree–level amplitudes, which gives rise to the idea of treating them simultaneously in a common Monte Carlo. Initially introduced for one–loop scalar integrals, the applicability of the LTD has been expanded to higher order loops and Feynman graphs beyond simple poles. For the...
German Sborlini
(IFIC-Valencia)
7/24/15, 3:45 PM
QCD and Hadronic Physics
talk
Loop-tree (LT) duality allows to express virtual contributions in terms of phase-space integrals, thus leading to a direct comparison with real radiation terms. In this talk, we review the basis of the method and describe its application to regularize Feynman integrals. Performing an integrand-level combination of real and virtual terms, we show that it is possible to recover physical results...
Martin Bessner
(Deutsches Elektronen-Synchrotron Hamburg and Zeuthen (DE))
7/24/15, 4:30 PM
QCD and Hadronic Physics
talk
Isolated prompt photons provide a direct probe of short-distance physics, complementary to that provided by measurements of jets or vector-bosons and are sensitive to the gluon density of the proton. The inclusive prompt photon cross sections have been measured by the ATLAS collaboration at 7 and 8 TeV pp collision centre-of-mass energies, over a wide range of transverse momenta. The diphoton...
Harald Ita
7/24/15, 4:45 PM
QCD and Hadronic Physics
talk
The study of vector-boson pair production in association with jets is one of
the key signatures for the analysis of the electroweak symmetry breaking
mechanism. While the vector bosons are the clear signs of electroweak dynamics,
the associated jets are important tags to suppress backgrounds and probe the
kinematic dependence of the interactions. At high jet multiplicity the
di-vector...
Markus Zinser
(Johannes-Gutenberg-Universitaet Mainz (DE))
7/24/15, 5:00 PM
QCD and Hadronic Physics
talk
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. Run-1 studies carried out by the ATLAS Collaboration are reviewed and first LHC Run-2...
Debarati Roy
(Saha),
Debarati Roy
(Saha Institute of Nuclear Physics (IN))
7/24/15, 5:15 PM
QCD and Hadronic Physics
talk
Recent results on jets measurements as well as jet properties and jet variables are presented.
Pavel Starovoitov
(Ruprecht-Karls-Universitaet Heidelberg (DE))
7/24/15, 5:30 PM
QCD and Hadronic Physics
talk
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...
Marco Peruzzi
(CERN)
7/24/15, 5:45 PM
QCD and Hadronic Physics
talk
The production of vector bosons (V = W, Z or γ) in association with jets is a stringent test of perturbative QCD and is a background process in searches for new physics. Total and differential cross-section measurements of vector bosons produced in association with jets and heavy flavour quarks in proton-proton collisions at the LHC are presented. The measurements are compared to next-to...
