Joel Feltesse
(DAPNIA)
26/03/2012, 09:10
Iris Abt
(Werner-Heisenberg-Institut)
26/03/2012, 09:50
Claude Marchand
(CEA - Centre d'Etudes de Saclay (FR))
26/03/2012, 11:40
David Waters
(University College London)
26/03/2012, 12:20
Markus Wobisch
(Louisiana Technical University (US))
26/03/2012, 14:35
Karin Daum
(University of Wuppertal/DESY)
26/03/2012, 15:15
Daniel De Florian
(Laboratorio de Fisica Teorica Departamento de Fisica)
26/03/2012, 15:55
Oliver Kortner
(Max-Planck-Institut fuer Physik (Werner-Heisenberg-Institut) (D)
26/03/2012, 17:00
Klaus Johannes Reygers
(Ruprecht-Karls-Universitaet Heidelberg (DE))
26/03/2012, 17:40
Barbara Clerbaux
(Universite Libre de Bruxelles (ULB)-Inter-University Institute f)
26/03/2012, 18:20
36.
Combined inclusive diffractive cross sections measured with forward proton
spectrometers at HERA
Valentina Sola
(Universita e INFN (IT))
27/03/2012, 09:00
Diffraction and vector mesons
A combination of the inclusive diffractive cross section measurements made by the H1 and ZEUS Collaborations at
HERA is presented. The analysis uses diffractive deep inelastic scattering data measured by means of proton spectrometers.
Correlations of systematic uncertainties are taken into account by the combination method,resulting in improved precision.
The combined data cover the range...
Werner Vogelsang
27/03/2012, 09:00
Spin physics
We give an overview of the recent developments
on longitudinal spin physics and the nucleon's
helicity structure. We highlight the status of
theoretical calculations and the impact of recent
data.
Hubert Spiesberger
(Univ. Mainz)
27/03/2012, 09:00
Heavy flavours
I present predictions for the inclusive production of D- and B-mesons
at the CERN LHC in the general-mass variable-flavor-number scheme
at next-to-leading order, an approach which takes into account the finite
mass of the heavy quarks. Numerical results are compared to data where
available. Measurements at large rapidities have the potential to pin down
models of intrinsic charm.
Oleg Kuprash
(DESY)
27/03/2012, 09:00
Hadronic final states
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...
Friederike Januschek
(DESY)
27/03/2012, 09:00
Structure functions
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...
Franz Herzog
(ETH Zurich)
27/03/2012, 09:00
Electroweak and searches
I will briefly review Standard Model Higgs production and decay
mechanisms and report on the status of the art of existing predictions, with major focus on the single Higgs production cross-section.
Claudia Gemme
(Universita e INFN (IT))
27/03/2012, 09:00
Adam Edward Barton
(Lancaster University (GB))
27/03/2012, 09:18
Heavy flavours
ATLAS has studied heavy flavour production in a variety of decay channels and inclusive
signatures including charmed mesons, jets originating from b-quarks and inclusive muons
and electrons. Differential production cross sections for beauty and charm are extracted
from these signatures and compared with a variety of theoretical predictions.
Dr
Prolay Kumar Mal
(CEA - Centre d'Etudes de Saclay (FR))
27/03/2012, 09:18
Electroweak and searches
The experimental results of the search for the Standard Model Higgs boson at the Large Hadron Collider (LHC) running at a centre-of-mass energy of 7 TeV are reported, based on a total integrated luminosity of up to 4.9 fb-1 collected by the ATLAS detector in 2011. The search combines several Higgs boson decay channels in the mass range from 110 GeV to 600 GeV and derives upper limits on the...
Stefan Schmitt
(Ruprecht-Karls-Universitaet Heidelberg (DE))
27/03/2012, 09:20
Structure functions
At HERA, deep inelastic scattering progresses have been studied in order to
probe the fundamental forces predicted by the standard model and the
structure of the proton. One of the most fundamental processes is the
elastic production of photons, e p -> e p gamma. For the case where the
momentum transfer at the proton vertex is small, but both the electron
and the photon have significant...
David Salek
(CERN)
27/03/2012, 09:20
Diffraction and vector mesons
First measurements are presented of the diffractive cross section
$\sigma_{ep \rightarrow eXY}$ at centre-of-mass energies $\sqrt{s}$ of
225 and 252 GeV, together with a precise new measurement at $\sqrt{s}$ of
319 GeV, using data taken with the H1 detector in the years 2006 and 2007.
Together with previous H1 data at $\sqrt{s}$ of 301 GeV, the measurements
are used to extract the...
27/03/2012, 09:20
Hadronic final states
Prompt isolated photon pairs production cross sections, as well as
direct photon production in association with a heavy (b or c) quark jets are presented.
Differential cross sections are presented as a function of several variables.
The results are compared with a next-to-leading order perturbative QCD calculations.
Thomas Peitzmann
(University of Utrecht (NL))
27/03/2012, 09:25
Future of DIS
Mr
Scott Wolin
(University of Illinois at Urbana-Champaign)
27/03/2012, 09:35
Spin physics
The determination of the gluon polarization within the proton, $\Delta G$, is one of the critical pieces to understanding the proton spin puzzle. Using collisions of polarized protons with $\sqrt{s}=200 \:GeV$ and $\sqrt{s}=500 \:GeV$ at the Relativistic Heavy Ion Collider (RHIC), PHENIX can access gluons and $\Delta G$ at leading order. Constraints on $\Delta G$ come from measurements of...
Emmanuel Sauvan
(LAPP (IN2P3/CNRS))
27/03/2012, 09:40
Diffraction and vector mesons
Measurements of the cross section for the diffractive process ep -> eXY are presented,
where Y is a proton or a low mass proton excitation carrying a fraction 1 − xIP > 0.95
of the incident proton longitudinal momentum and the squared four-momentum transfer
at the proton vertex satisfying MY < 1.6 GeV and |t| < 1.0 GeV^2. Using data taken
by the H1 experiment, the cross section is measured...
Nikolai Skachkov
(Joint Inst. for Nuclear Research (RU))
27/03/2012, 09:40
Hadronic final states
Photon+jets measurements in ppbar Collisions at D0
Uta Klein
(University of Liverpool (GB))
27/03/2012, 09:40
Structure functions
Merged abstract:
"W/Z production at ATLAS, and constraints on parton density functions"
"QCD analysis of the ATLAS W-> lnu and Z ->ll cross-sections measurements and determination of the strange sea density"
Pietro Govoni
(CERN)
27/03/2012, 09:42
Electroweak and searches
We present results of the search for the standard model Higgs boson
at CMS.
Renaud Le Gac
(Universite d'Aix - Marseille II (FR))
27/03/2012, 09:50
Future of DIS
The LHCb experiment is designed to perform high-precision measurements of CP violation and search for New Physics using the enormous flux of beauty and charmed hadrons produced at the LHC. The operation and the results obtained from the data collected in 2010 and 2011 demonstrate that the detector is robust and functioning very well. However, the limit of 1 fb$^{-1}$ of data per year cannot be...
Rosa Romita
(GSI - Helmholtzzentrum fur Schwerionenforschung GmbH (DE))
27/03/2012, 09:54
Heavy flavours
ALICE is the LHC experiment dedicated to the study of the Quark Gluon Plasma (QGP)
in Pb-Pb collisions. Heavy quarks are ideal probes to explore the QGP formation and
properties, since they experience the full collision history and are expected to be
abundantly produced at the LHC. It is of great importance to measure the heavy flavor
cross section not only in Pb-Pb collisions, but also in...
Richard Polifka
(University of Toronto (CA))
27/03/2012, 10:00
Diffraction and vector mesons
The cross section of diffractive deep-inelastic scattering ep \rightarrow eXp
is measured, where the system X contains at least two jets and the leading
final state proton is detected in the H1 Forward Proton Spectrometer. The
measurement is performed for fractional proton longitudinal momentum loss
xIP < 0.1 and covers the range 0.1 < |t| < 0.7 GeV2 in squared four-momentum
transfer...
Marcin Stolarski
(LIP Laboratorio de Instrumentacao e Fisica Experimental de Part)
27/03/2012, 10:00
Spin physics
A short review of the COMPASS results concerning gluon polarization
inside the nucleon, DG/G, is given including two new measurements:
Firstly, a DG/G determination in leading order and in three bin of
the gluon momentum fraction x_g from asymmetries in high-p$_T$
hadron pair production for Q$^2>$1 (GeV/c)$^2$;
secondly, a preliminary next-to-leading order analysis
based on open charm...
Leonardo Carminati
(Università degli Studi e INFN Milano (IT))
27/03/2012, 10:00
Hadronic final states
Isolated prompt photons provide a direct probe of short-distance physics, complementary to
that provided by measurements of jets or vector-bosons. The inclusive prompt photon cross
section has been measured over a wide range of transverse momenta; the diphoton cross section
has also been measured as a function of diphoton mass, total transverse momentum and azimuthal
separation; the cross...
Kyle Knoepfel
(F)
27/03/2012, 10:06
Electroweak and searches
We present results from the search for a standard model Higgs boson using up to 10/fb of proton-antiproton collision data produced by the Fermilab Tevatron at a center-of-mass energy of 1.96 TeV. The data were recorded by the CDF and D0 Detectors between March 2001 and September of 2011. Updated results from many exclusive channels as well as the combined Tevatron search are presented.
Krzysztof Nowak
(Deutsches Elektronen-Synchrotron (DE))
27/03/2012, 10:10
Structure functions
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.
Antoni Szczurek
(Cracow, INP & Rzeszow Univ.)
27/03/2012, 10:12
Heavy flavours
We discuss charm production at LHC. The production of single $c \bar c$ pairs
is calculated in the $k_t$-factorization approach. We use several
unintegrated gluon distributions from the literature. Some of them
include effect of small-$x$ saturation and fulfill Balitsky-Kovchegov
evolution equation. The hadronization is included with the help of
fragmentation functions found for the...
Aleksandr Azatov
27/03/2012, 11:00
Electroweak and searches
A review the status of the BSM Higgs (excluding supersymmetry) with particular emphasis on the composite Higgs, the connection to light custodians.
Karol Kovarik
(KIT)
27/03/2012, 11:00
Heavy flavours
The production of a prompt photon in association with a heavy-quark (charm or bottom) jet is a versatile process that can be used to study the structure of the proton and the nucleus. This process is extremely sensitive to the heavy quark PDFs, and can thus directly probe for intrinsic charm or bottom contributions. We present various predictions of this process at different colliders and...
Dr
maria ubiali
(University of Edinburgh)
27/03/2012, 11:00
Structure functions
A determination of parton distribution functions with reliable estimation of associated uncertainties is a key ingredient for exploiting the full physics potential of the experiments at the LHC collider. On the other hand, measurements from the LHC will provide important constraints on PDFs in kinematic regions which are so far not covered by data included in global analyses. In this talk I...
Andrea Banfi
(Freiburg U)
27/03/2012, 11:00
Hadronic final states
We present accurate (NLL+NNLO) predictions for jet-veto efficiencies for Higgs and Z production at the LHC, obtained with the automated resummation program CAESAR. We discuss all sources of theoretical uncertainties associated to the presented results, highlighting which further calculations would be needed in order to reduce them.
Federico Alberto Ceccopieri
(Fondazione Angelo Della Riccia Ente Morale)
27/03/2012, 11:00
Diffraction and vector mesons
A new method for the extraction of diffractive parton distributions is presented which avoids the use of Regge theory ansatz and is in much closer relation with the factorization theorem for diffractive hard processes.
Piet J Mulders
(VU University)
27/03/2012, 11:00
Spin physics
Transverse momentum dependent (TMD) distribution and fragmentation functions are described as Fourier transforms of matrix elements containing non-local combinations of quark and gluon fields. While the collinear functions are light-cone correlators in which the non-locality is restricted along the light-cone, the transverse momentum dependent functions are light-front correlators including a...
Piotr Kotko
27/03/2012, 11:18
Heavy flavours
We present the consistent treatment of heavy quarks in jet production processes in DIS at NLO accuracy. The method is based on the ACOT massive factorization scheme (Aivazis-Collins-Olness-Tung) which is already in use in global fits for PDFs. Extension of this method to jets faces the problem of infra-red singularities, which have to cancel between real and virtual corrections. Moreover,...
Javier Fernandez Menendez
(Universidad de Oviedo (ES))
27/03/2012, 11:18
Electroweak and searches
We present results of searches for the non-standard-model Higgs bosons
at CMS.
Mrs
Sara Taheri Monfared
(Semnan university and IPM)
27/03/2012, 11:20
Diffraction and vector mesons
We extract diffractive parton distribution functions (DPDFs) and diffractive structure functions from the most recent H1 and ZEUS diffractive DIS data obtained by various methods. We consider Pomeron as an object with parton distribution function, evolving according to the next-to-leading order (NLO) DGLAP equations within the framework of the ‘Fixed Flavour Number Scheme’ (FFNS). Having...
Peter Schichtel
(ITP)
27/03/2012, 11:20
Hadronic final states
The properties of jets are used in many LHC physics searches. Higgs
searches use jet vetoes and fixed recoil jet multiplicities. Searches
for new physics particles require a careful distinction of decay jets
from QCD jet radiation. We show that the exclusive number of jets
at hadron colliders can be described with two simple patterns: staircase scaling and Poisson scaling. In photon plus...
Sergey Alekhin
27/03/2012, 11:25
Structure functions
We present a determination of the nucleon parton distribution functions (ABM11) and the strong coupling constant $\alpha_s$ at next-to-next-to-leading order (NNLO) in QCD based on world data for deep-inelastic scattering and fixed-target data for Drell-Yan process. The analysis is performed in the fixed-flavor number scheme for $n_f=3,4,5$ and uses the \MSbar scheme for $\alpha_s$ and the...
Christoph Adolph
(Friedrich-Alexander-Univ. Erlangen (DE))
27/03/2012, 11:35
Spin physics
The quark content of the nucleon at twist-two level in the collinear case can be fully characterized by three independent distribution functions for each quark flavour: the unpolarized distribution function f1(x), the helicity distribution function g1(x) and the transverse spin distribution function h1(x), also called transversity.
The measurements of single spin asymmetries in semi-inclusive...
David Calvet
(Univ. Blaise Pascal Clermont-Fe. II (FR))
27/03/2012, 11:36
Heavy flavours
The inclusive and dijet production cross-sections have been measured for jets containing b-hadrons (b-jets)
in proton-proton collisions at a centre-of-mass energy of sqrt(s) = 7 TeV.
The b-jets are identified using either a lifetime-based method, where secondary decay vertices of
b-hadrons in jets are reconstructed using information from the tracking detectors, or a muon-based
method...
Bruno Lenzi
(CERN)
27/03/2012, 11:36
Electroweak and searches
The discovery of a neutral Higgs boson with large decay branching fraction to tau and muon pairs, as well as the discovery of a charged Higgs boson would represent a strong evidence of new physics beyond the Standard Model. The experimental results of the searches for the Higgs bosons beyond the Standard Model with the ATLAS detector are reported. The searches are based on an integrated...
Mariusz Sadzikowski
(Jagiellonian University)
27/03/2012, 11:40
Diffraction and vector mesons
HERA data on diffractive DIS show deviations from twist 2 DGLAP predictions below Q^2 5 GeV^2 at low x_P, which may reach up to 100%. These deviations are consistent with higher twists effects extracted from the saturation model. It is a first direct evidence for the higher twists in DIS. This finding affects determination of the diffractive parton densities that are used for the predictions...
Adam Yurkewicz
(Northern Illinois University (US))
27/03/2012, 11:40
Hadronic final states
Differential jet cross sections and distributions have been measure inclusively, in dijet events
and in multijet events, using information from the ATLAS calorimeters and tracking detectors. The inclusive
jet measurements extend from 20 GeV to 1.5 TeV, and the dijet measurements cover a very wide mass range.
Measurements based on tracking alone are sensitive only to the charged-particle...
Pedro Jimenez-Delgado
(Jefferson Lab)
27/03/2012, 11:50
Structure functions
Different theoretical improvements and the inclusion of alternative data sets in the determination of dynamical parton distribution functions are reported. Highlights in the ongoing developments as well as the role of the input scale in parton analysis are discussed.
Dr
Markus Diefenthaler
(University of Illinois at Urbana-Champaign)
27/03/2012, 11:50
Future of DIS
The E-906/SeaQuest experiment at Fermilab will continue a series of Drell-Yan measurements to explore the antiquark structure of the nucleon and nuclei. To extend existing measurements to larger values of Bjorken-x, a 120 GeV proton beam extracted from Fermilab's main injector is used, resulting in a factor of 50 more luminosity than previous experiments and enabling access to values of x up...
Zlatka Georgieva Staykova
(University of Antwerp (BE))
27/03/2012, 11:54
Heavy flavours
The inclusive photoproduction of D* mesons and of D*-tagged dijets is investigated with the H1 detector at the $ep$ collider HERA. The kinematic region covers small photon virtualities $Q^{2} < 2\ {\rm GeV}^2$ and photon-proton centre-of-mass energies of $100 < W_{\gamma p} < 285\ {\rm GeV}$. Inclusive \dstar\ meson differential cross sections are measured for central rapidities $|\eta(D*)| <...
Valentina Santoro
(University of Ferrara)
27/03/2012, 11:54
Electroweak and searches
Several types of new-physics models predict the existence of low-mass Higgs states. Previous BABAR searches for leptonic and invisible light-Higgs decays have excluded large regions of model parameter space. We present new searches for hadronic Higgs decays and for a dark-sector Higgs produced in association with a dark gauge boson.
Leszek Motyka
(Jagellonian Univerisity)
27/03/2012, 12:00
Diffraction and vector mesons
We present new results on determination of higher twist contributions in diffractive DIS and compare them to the inclusive DIS case. In both cases the framework for the estimates is provided by the saturation model. We discuss the methods of higher twist extraction from the saturation model and compare the results for DIS and DDIS. We point out a striking difference in higher twist importance...
Francesca Giordano
(U)
27/03/2012, 12:00
Spin physics
The azimuthal $\cos\phi$ and $\cos2\phi$ modulations of the distribution of hadrons produced in unpolarized semi-inclusive deep-inelastic scattering of electrons and positrons off hydrogen and deuterium targets have been measuread at the HERMES experiment.
For the first time these modulations were determined in a four-dimensional kinematic space for positively and negatively charged pions and...
Thomas Schoerner-Sadenius
(Deutsches Elektronen-Synchrotron (DE))
27/03/2012, 12:00
Hadronic final states
Jets and multi-jets at large rapidities in p-p collisions at the LHC
Emilien Chapon
(Centre d'Etudes de Saclay (CEN Saclay)-Unknown-Unknown)
27/03/2012, 12:12
Electroweak and searches
In Beyond Standard Model (BSM) theories such as supersymmetry,
the electroweak symmetry breaking mechanism predicts one or
several Higgs bosons with different couplings and masses compared to the Standard Model one. We will present the constraints on BSM theories coming from searches for exotic Higgs bosons from the CDF and D0 collaborations at the Tevatron. In addition, other bump searches...
Irakli Garishvili
(Lawrence Livermore Nat. Laboratory (US))
27/03/2012, 12:12
Heavy flavours
Heavy flavor quarks are produced in the early stages of heavy ion
collisions and serve as an important probe of the strongly interacting
deconfined medium believed to be produced in these collisions at RHIC.
Measuring observables such as Nuclear Modification Factor and Elliptic
Flow for open heavy flavor production can help in quantifying medium
effects.
Measurement of heavy flavor...
Dr
Gerhard Mallot
(CERN)
27/03/2012, 12:15
Future of DIS
COMPASS at CERN is preparing for a new series of measurements on the nucleon structure comprising deep virtual Compton scattering and hard exclusive meson production using muon beams, as well as Drell-Yan reactions using a polarised proton target and a negative pion beam. The former will mainly constrain the generalized parton distribution H and determine the transverse size of the nucleon,...
290.
Uncertainties in Determining Parton Distributions at Large x: Results from the CJ Collaboration
Cynthia Keppel
(Hampton University)
27/03/2012, 12:15
Structure functions
The results of a global next-to-leading order fit of parton
distribution functions in which cuts on W and Q are relaxed, thereby
including more data at high values of x, will be reported. Effects of
target mass corrections (TMC), higher twist contributions, and nuclear
corrections for deuterium data are significant in the large-x region.
The leading twist parton distributions are found to...
Jennifer Smillie
27/03/2012, 12:20
Hadronic final states
The theoretical description of multi-jet final states is an issue of
great importance at the LHC. The High Energy Jets (HEJ) framework
offers a new approach to this and provides an all-order resummation of
the dominant contributions from wide-angle QCD radiation. I will give a
brief introduction to the framework and then show comparisons to early
data from ATLAS and CMS analyses and...
Johannes Bluemlein
(DESY)
27/03/2012, 12:35
Structure functions
We report on a QCD re-analysis of the unpolarized non-singlet world data data in the valence region up to $O(\alpha_s^{3(4)})$ correlated to the value of the strong coupling constant $\alpha_s(M_Z2)$ and the higher twist contributions. We investigate contributions of twist $\tau = 3$ and higher to the polarized structure functions $g_1(x,Q2)$ and $g_2(x,Q2)$.
Dr
Erik Brücken
(Helsinki Institute of Physics (FI))
27/03/2012, 14:00
Diffraction and vector mesons
We report central exclusive production results studied at the Run II Collider Detector at Fermilab with focus on our recently published paper on the first observation of exclusive γγ production in pp ̄ collisions at √s = 1.96 TeV at the Tevatron. In particular, starting from earlier studies by the CDF collaboration, we discuss exclusive dijet, dilepton, Z, J/Ψ and χc productions and finally...
Ganna Dolinska
(Kiev University)
27/03/2012, 14:00
Heavy flavours
The production of D*, D+, D0, Ds and Lambda_c charm hadrons and their antiparticles in ep scattering at HERA was studied with the ZEUS detector using the full HERA II data set. The measurement has been performed in the photoproduction regime. The fractions of c quarks hadronising as a particular charm hadron, f(c -> D, Lambda_c), were derived in the visible kinematic range. The obtained...
Pavel Nadolsky
(Southern Methodist University)
27/03/2012, 14:00
Structure functions
I discuss latest developments in the CTEQ-TEA PDF analysis: NNLO PDFs, benchmarking of NLO and NNLO cross sections included in the global fits, analysis of constraints on PDFs with the method of PDF-induced correlations.
Ennio Salvioni
(Universita e INFN (IT))
27/03/2012, 14:00
Electroweak and searches
We present the implications of recent LHC results on some classes
of Z' and W' models. We also remark how the strongest bounds
(coming for example from searches for Z' -> dileptons and W' ->
lepton + neutrino) do not apply to some theoretically motivated
resonances, and discuss where signals from such states would
appear.
Nikolai Skachkov
(Joint Inst. for Nuclear Research (RU))
27/03/2012, 14:00
Hadronic final states
W/Z+jets measurements at D0
Martin Weber
(Rheinisch-Westfaelische Tech. Hoch. (DE))
27/03/2012, 14:18
Electroweak and searches
Searches for new physics with leptons and/or jets at CMS
Alexander Mitov
(CERN)
27/03/2012, 14:18
Heavy flavours
The current state of the art in top-pair production is based on threshold resummation on top of the exact NLO result. We will examine the role - and the limitations - of the soft-gluon approximation in describing precision top-pair production at hadron colliders. We will demonstrate that the only way to substantially improve our knowledge of this observable is through fixed order calculation...
Dermot Moran
(Univ Manchester)
27/03/2012, 14:20
Diffraction and vector mesons
We report on studies of exclusive dimuon production, using LHCb experimental data. Exclusively produced muon pairs can be produced by two photon fusion (a QED process ideally suited to obtaining a precise integrated luminosity measure), or by resonance production. We show results for exclusive dimuon production, and observations of the exclusive J/psi. psi‘ and chi_c states, obtained with data...
Lorenzo Ortolan
27/03/2012, 14:20
Hadronic final states
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 $\sim 9$ fb$ ^{-1}$ of data in $\rm p\bar{p}$ collisions at $\rm \sqrt{s}$ = 1.96 TeV collected with the CDF detector in Run II.
Differential cross sections...
Rodolfo Sassot
(Universidad de Buenos Aires)
27/03/2012, 14:25
Structure functions
We present a new global QCD analysis of nuclear parton distribution functions
and their uncertainties. In addition to the most commonly analyzed data sets
for deep inelastic scattering of charged leptons off nuclei and Drell-Yan di-lepton production, we include also measurements for neutrino nuclei scattering as well as inclusive pion production in deuteron gold collisions.
The analysis is...
Nikolaos Kidonakis
(Kennesaw State University)
27/03/2012, 14:36
Heavy flavours
I present theoretical results at approximate NNLO for top quark production at the LHC at 7 and 8 TeV energy. Total cross sections are shown for ttbar production and single top production in the t and s channels and via associated tW production.Top quark transverse momentum and rapidity distributions are also presented.
Antonio Policicchio
(INFN Cosenza)
27/03/2012, 14:36
Electroweak and searches
We present the most recent results of searches beyond the Standard Model with leptons and /or jets conducted by the ATLAS collaboration based on several inverse femtobarns of data.
Wenbo Li
(Peking University (CN))
27/03/2012, 14:40
Diffraction and vector mesons
We present the search for exclusive diphoton production and
the measurement of exclusive dilepton production, based on the data
recorded by the CMS experiment at the LHC in 2010. An upper limit on the
cross section is set for exclusive diphoton production, which is
compared with the QCD perturbative theory predictions using different
PDF sets. The exclusive dielectron production provides...
Camille Belanger-Champagne
(McGill University (CA))
27/03/2012, 14:40
Hadronic final states
The production of jets in association with a W or Z boson in proton-proton collisions at 7 TeV
is an important process to understand in QCD. The cross section, differential in several kinematics variables,
has been measured up to high jet multiplicities and compared to new higher-order QCD calculations. The ratio
of (Z + a single jet)/(W + a single jet) can provide a very precise test of...
Karol Kovarik
(University of Karlsruhe)
27/03/2012, 14:45
Structure functions
A global NPDF analysis of the combined charged-lepton DIS, DY and
neutrino DIS data finds a tension between the nuclear correction
factors in nA DIS and ℓA DIS. We explore possible sources of this
tension by comparing the input PDFs used by different nuclear global
fitting groups, and also compute ratios of experimental observables
which (largely) minimize any theoretical bias. We also...
Dr
Salvatore Fazio
(Brookhaven National Laboratory)
27/03/2012, 14:50
Future of DIS/spin physics
none
Kate Shaw
(Abdus Salam Int. Cent. Theor. Phys. (IT))
27/03/2012, 14:54
Heavy flavours
We present measurements of the production of top quarks in
proton-proton collisions at 7 TeV with the ATLAS detector at the Large
Hadron Collider. The cross section of pair-produced top quarks is
measured in several channels, including the single lepton, dilepton
and all hadronic channel, some using information from b-tagging.
Sushil Chauhan
(University of California Davis (US))
27/03/2012, 14:54
Electroweak and searches
Searches for large extra dimensions, Leptoquarks and heavy quarks at CMS
Dr
Marek Tasevsky
(Acad. of Sciences of the Czech Rep. (CZ))
27/03/2012, 15:00
Diffraction and vector mesons
We investigate the prospects for Central Exclusive Diffractive (CED)
production of BSM Higgs bosons at the LHC using forward proton detectors installed at 220~m and 420~m distance around ATLAS and / or CMS.
We update a previous analysis for the MSSM taking into account
improvements in the theoretical calculations and the most
recent exclusion bounds from the LHC.
We extend the MSSM...
Frank Siegert
(Albert-Ludwigs-Universitaet Freiburg (DE))
27/03/2012, 15:00
Hadronic final states
The MC@NLO method as implemented in the Sherpa MC generator is
presented using the production of W-bosons in conjunction with up to
three jets as an example. Corresponding results computed at next-to
leading order in QCD and including parton shower corrections are
compared to recent experimental data from the Large Hadron Collider.
Clara Salas
(IFT, Madrid)
27/03/2012, 15:05
Structure functions
The proton structure function F_2 is studied in the low x regime using BFKL evolution instead of the usual DGLAP approach,
suited for large values of the DIS x variable. The NLL analysis requires the inclusion of running coupling effects which lead to
off-diagonal terms in the BFKL kernel that need to be treated carefully. We also introduce an all-orders resummation that improves
the...
Antonio Tropiano
(Universita e INFN (IT))
27/03/2012, 15:12
Heavy flavours
We present precise measurements of the top quark pair production cross
section at 7 TeV, performed using CMS data collected in 2010-2011. The
total cross section is measured in the lepton+jets, dilepton and fully
hadronic channels, including the tau-dilepton and tau+jets modes. The
results are combined and confronted with precise theory calculations. We
also obtain an indirect constraint...
Dr
Loic Quertenmont
(CERN)
27/03/2012, 15:12
Electroweak and searches
Search for heavy stable particles in CMS
Dieter Mueller
(BNL and Ruhr-University Bochum)
27/03/2012, 15:15
Future of DIS/spin physics
We discuss the access of generalized parton distributions (GPDs) from deeply virtual
Compton scattering (DVCS) and deeply virtual
meson production. We also illustrate that DVCS measurements at a future high-luminosity
electron-ion-collider provide insight in both the transverse distribution of sea quarks
and gluons as well as the...
Adrien Besse
(L)
27/03/2012, 15:20
Diffraction and vector mesons
Exclusive leptoproduction of vector mesons has been the subject of recent significant progress, both theoretically and experimentally. In particular, the hard regime with a highly virtual photon exchange allows to separate a short distance dominated amplitude of hard subprocess from suitably defined hadronic objects. However, a consistent picture is still missing, in particular for...
Stefan Prestel
(L)
27/03/2012, 15:20
Hadronic final states
We present the recent implementation of CKKW-L merging inside Pythia8, and comment on the treatment of multiparton interactions in the context of matrix element merging. Since multiple interactions inside Pythia8 are
fully interleaved with space- and time-like showers, care has to be taken
when allowing for MPI. Further, we will discuss the uncertainties of the
implementation.
Hannes Jung
(Deutsches Elektronen-Synchrotron (DE))
27/03/2012, 15:25
Structure functions
We present a new determination of the un-integrated PDF using
the combined HERA data. We obtain acceptable chi*2/ndf.
We find that for a good description of HERA data the gluon splitting
function including non-singular terms as well as kinematic constraints
and NLO alphas are necessary. We determine for the first time a
full set of uncertainty uPDFs which allow to study the uPDF...
Jiahang Zhong
(University of Oxford (GB))
27/03/2012, 15:30
Electroweak and searches
The addition of one or more heavy quarks is a natural extension to the Standard Model.
Fourth generation heavy quarks can be produced at the LHC at rates that can be observed in the 2011 data samples.
The talk presents results from searches\'a0performed by the ATLAS collaboration for fourth generation quarks decaying via several potential decay channels.
Karel Soustruznik
(C)
27/03/2012, 15:30
Heavy flavours
We present measurements of the cross sections for the production
of top-antitop quark pair production via the strong interaction and
for the production of single top quarks via the weak interaction in
proton-antiproton collisions at sqrt(s)=1.96 TeV using data
corresponding to integrated luminosities of up to 5.4 fb-1. The data
were collected with the D0 detector at the Fermilab Tevatron...
Marco Stratmann
(Univ. Regensburg/Univ. Wuerzburg)
27/03/2012, 15:40
Future of DIS/spin physics
none
Simon Plaetzer
(DESY Hamburg)
27/03/2012, 15:40
Hadronic final states
Parton shower Monte Carlos are by now standard tools to simulate
hadronic final states. Having seen a tremendous improvement of
combining parton showers and fixed order calculations in recent years,
efforts are now underway to improve the shower approximations
themselves, as well.
In this contribution we will present first steps towards including
subleading colour contributions into...
Emilien Chapon
(Centre d'Etudes de Saclay (CEN Saclay)-Unknown-Unknown)
27/03/2012, 15:40
Diffraction and vector mesons
We study the W/Z pair production via two-photon exchange at the LHC and give the sensitivities on trilinear and quartic gauge anomalous couplings between photons and W/Z bosons. Tagging the protons in the final state in the ATLAS Forward Physics detectors as an example allows to improve the reach on anomalous couplings by four orders of magnitude reaching the values predicted by...
Konstantinos Vellidis
(University of Athens (GR))
27/03/2012, 15:48
Heavy flavours
The study of the dynamics of top-quark pair production in
proton-proton and proton-antiproton collisions plays an important role
in the understanding of parton interactions at large Bjorken-x. It
tests the assumptions of the standard model and of quantum
chromodynamics at the electroweak scale and beyond. The CDF data set
is an ideal sample for measuring observables sensitive to the...
Christian Andreas Jung
(TU Dortmund),
Christian Andreas Jung
(Technische Universitaet Dortmund (DE))
27/03/2012, 16:30
Heavy flavours
We present a measurement of the top-quark mass in proton-proton
collisions at 7 TeV with the ATLAS detector at the Large Hadron
Collider. The top mass is determined by making use of a
two-dimensional template method in the single lepton channel. An
indirect extraction of the top-quark mass from the measurement of the
cross-section is also presented.
Torben Ferber
(Hamburg University)
27/03/2012, 16:30
Electroweak and searches
The OPERA neutrino experiment at the underground Gran Sasso Laboratory has measured the velocity of neutrinos from the CERN CNGS beam over a baseline of about 730 km with much higher accuracy than previous studies conducted with accelerator neutrinos. The measurement is based on high-statistics data taken by OPERA in the years 2009, 2010 and 2011. Dedicated upgrades of the CNGS timing system...
Giovanni Antonio Chirilli
(Lawrence Berkeley National Laboratory (LBNL))
27/03/2012, 16:30
Structure functions
I will present an analytic expression in momentum space of the next-to-leading order photon impact factor for small-x deep inelastic scattering. The result is calculated using the operator product expansion in Wilson lines.
Prof.
Bernd Surrow
(MIT)
27/03/2012, 16:30
Spin physics
The STAR experiment at the Relativistic Heavy-Ion Collider at Brookhaven National
Laboratory is carrying out a spin physics program in high-energy polarized proton collisions at $\sqrt{s}=200\,$GeV and $\sqrt{s}=500\,$GeV
to gain a deeper insight into the spin structure and
dynamics of the proton.
The completion of the first $\sqrt{s}=500\,$GeV polarized proton run in 2009 opened a new...
Benedikt Zihlmann
(J)
27/03/2012, 16:30
Dr
Michal Deak
(Universidade de Santiago de Compostela)
27/03/2012, 16:30
Hadronic final states
We present a subtraction method for including next to leading order corrections to a 2 to 2 jet production process in kt-factorisation equivalent to a jet matching procedure in Monte Carlo generators. We study the improvement in soft cut dependance.
Prof.
Otto Nachtmann
(Institute for Theoretical Physics, University of Heidelberg)
27/03/2012, 16:45
Structure functions
The DIS structure functions are expressed, in a rigorous way, as correlation functions in a quantum field theory containing a parameter r. It is shown that low x physics corresponds to the theory in the limit of r going to zero where the theory develops a large correlation length. This indicates critical behaviour. The data on F2 are analysed in a geometric way and values for the critical...
Sergey Sibiryakov
(Institute for Nuclear Research of RAS)
27/03/2012, 16:48
Electroweak and searches
We review the theoretical implications of the OPERA results, with particular emphasis on the consistency with other tests of special relativity (directly or through quantum effects in the charged lepton sector) and the difficulties in construction of models satisfying all constraints.
Tim Head
(The University of Manchester),
Timothy Head
(University of Manchester)
27/03/2012, 16:48
Heavy flavours
Merged abstract:
"Measurement of the top quark mass at D0"
"Measurements of top quark properties at D0"
Mr
Maxim Malyshev
(SINP MSU)
27/03/2012, 16:50
Hadronic final states
In the framework of the kt-factorization approach, the production of unpolarized Drell-Yan lepton pair at high energies is studied. The consideration is based on the O(alpha) and $O(alpha alpha_s) off-shell partonic matrix elements with virtual photon and Z boson exchange. The calculations include leptonic decays of Z bosons with full spin correlations as well as gamma - Z interference. The...
Antonio Vilela Pereira
(Universita e INFN (IT))
27/03/2012, 16:50
Diffraction and vector mesons
The talk will present CMS measurements on diffractive W and
dijet production in p-p collisions at 0.9, 2.36 and 7 TeV.
Keith Griffioen
(C)
27/03/2012, 16:55
Future of DIS
With the doubling of the Jefferson Lab beam energy and the complete rebuilding of the CLAS spectrometer underway, a full experimental program is already approved for Hall B. The components of this program relevant to deep-inelastic scattering will be discussed.
Emanuele Roberto Nocera
(Universita degli Studi di Milano and INFN, Milano)
27/03/2012, 17:00
Spin physics
We present a preliminary determination of a set of polarized parton
distributions of the nucleon, at next-to-leading order, from a global set of
deep-inelastic scattering data. The determination is based on the NNPDF
methodology: a Monte Carlo sampling with neural networks used as unbiased
interpolants. This method, which has already been applied to a...
Carlo Ewerz
(ExtreMe Matter Institute EMMI, GSI, and Heidelberg University)
27/03/2012, 17:00
Structure functions
From the new measurement of F_L at HERA we derive fixed-Q^2 averages <F_L/F_2>. We compare these with bounds which are rigorous in the framework of the standard dipole picture. The bounds are sharpened by including information on the charm structure function F_2^(c). Within the experimental errors the bounds are respected by the data. But for 3.5 GeV^2 <= Q^2 <= 20 GeV^2 the central values of...
Minoru Hirose
(Osaka University (JP)),
Minoru Hirose
(Osaka University)
27/03/2012, 17:06
Heavy flavours
Merged abstract:
"Top quark properties"
"Top quark pair properties"
Hayk Pirumov
(PI Heidelberg)
27/03/2012, 17:06
Electroweak and searches
Merged abstract of:
"Search for Contact Interactions in ep Collisions at HERA"
"Search for First Generation Leptoquarks in ep Collisions at HERA"
Daniel Wilhelm
(Mainz U)
27/03/2012, 17:10
Hadronic final states
We discuss the differential cross sections for electroweak gauge-boson and Higgs production at small and very small transverse momentum q_T.
Large logarithms are resummed using soft-collinear effective theory.
The collinear anomaly generates a non-perturbative scale q^∗, which protects the processes from receiving large long-distance hadronic contributions. A numerical comparison of our...
Dr
Mickey Chiu
(Brookhaven National Lab)
27/03/2012, 17:10
Diffraction and vector mesons
One of the fundamental goals of the PHENIX experiment is to understand the structure of cold nuclear matter, since this serves as the initial state for heavy-ion collisions. Knowing the initial state is vital for interpreting measurements from heavy-ion collisions. Moreover, the structure of the cold nucleus by itself is interesting since it is a test-bed for our understanding of QCD. In...
Dr
Polina Kravchenko
(DESY)
27/03/2012, 17:20
Spin physics
Final measurements are reported on the double-spin asymmetries for a longitudinally polarized hydrogen and deuterium targets at HERMES using the27.6 GeV HERA lepton beam. The kinematic dependences of the longitudinal semi-inclusive asymmetry simultaneously on Bjorken-x and hadron transverse momentum p_h, and Bjorken-x and the hadron energy fraction z are explored. Additionally, the hadron...
Krzysztof Kutak
(I)
27/03/2012, 17:20
Structure functions
Motivated by the explored nowadays at LHC the regime of QCD where both the total energy of collision and momenta transfers are high, we investigate evolution equations of high energy factorization. In order to study such effects like parton saturation in final states one is inevitably lead to investigate how to combine physics of the BK and CCFM evolution equations. In this letter we obtain a...
Mr
Kalyan Allada
(Jefferson Lab)
27/03/2012, 17:20
Future of DIS
One of the cleanest ways to access the Transverse Momentum Dependent (TMD) parton distribution functions of the nucleon is to measure single (SSA) and double spin asymmetries (DSA) in semi-inclusive DIS reactions using polarized nucleon targets. The Jefferson Lab 12 GeV upgrade will provide a unique opportunity to perform such precision measurements and to map these multi-dimensional PDFs. In...
Stefano Antonelli
(Universita e INFN)
27/03/2012, 17:24
Electroweak and searches
Merged abstract of:
"Search for Single-Top Production in ep Collisions at HERA"
"A search for resonance decays to lepton+jet at HERA and limits on leptoquarks"
Sven-Olaf Moch
(Unknown)
27/03/2012, 17:24
Heavy flavours
We discuss heavy-flavor production in association with one jet
hadronic collisions matched to parton shower Monte Carlo programs at next-to-leading order QCD with account of top-quark decays
and spin correlations in the decay products.
The calculation builds on existing results for the radiative corrections to heavy-quark plus one jet production and uses the POWHEG BOX for the interface to...
Prof.
Antoni Szczurek
(Institute of Nuclear Physics Krakow (Poland))
27/03/2012, 17:30
Diffraction and vector mesons
We discuss central exclusive production of $W^+W^-$ pairs in proton-proton collisions at LHC. Several observables related to this
process are calculated. Predictions for the total cross section and differential distributions in rapidity and transverse momentum of $W^{\pm}$ and $WW$ invariant mass are presented.
We show results for different polarization states of the final $W^{\pm}$ bosons....
Jason Gallicchio
(UC Davis)
27/03/2012, 17:30
Hadronic final states
Distinguishing light-quark jets from gluon jets on an event-by-event basis could significantly enhance the reach for many new physics searches at the Large Hadron Collider. Through an exhaustive search of existing and novel jet substructure observables, we find that a multivariate approach can filter out over 95% of the gluon jets while keeping more than half of the light-quark jets. Moreover,...
Franco Buccella
(Unknown)
27/03/2012, 17:35
Structure functions
First we recall the basic physical features of the parton distribution functions (PDF) in the quantum statistical approach of the nucleon. Several predictions from next-to-leading QCD calculations
using these PDF are compared with recent experimental results: deep inelastic scattering from
HERA, hadronic reactions from Tevatron and RHIC, neutrino data and also polarized data obtained
by...
Young Jin Kim
(University of Illinois at Urbana-Champaign)
27/03/2012, 17:40
Spin physics
A major direction of the physics program at the Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory (BNL) is to explore the origin of proton spin structure. Parity violating single spin asymmetries, $A_L$, for $W$-bosons in longitudinally polarized $p + p$ collisions at a center of mass energy of $\sqrt{s}$ = 500 GeV will give access to the flavor separated quark and...
Mauro Piccini
(Universita e INFN (IT))
27/03/2012, 17:42
Electroweak and searches
Merged abstract:
"High precision measurement of the form factors of the semileptonic decays K+- -> pi0 l+- nu (Kl3)"
"Rare kaon decay measurements with NA62 minimum bias data."
"First Measurement of the very rare Decay K+ -> pi+ pi0 e+ e-"
"Lepton Universality Tests in Kaon Decays at NA62"
Adam Kardos
(University of Debrecen)
27/03/2012, 17:42
Heavy flavours
Aiming at better understanding of the properties of top quarks, we focus on top--antitop+X production at the LHC, with X being a vector, or scalar/pseudoscalar boson. We show predictions obtained by PowHel, a
computing framework based upon the POWHEG-BOX program with input
obtained from HELAC-NLO. The POWHEG-BOX generates event files
according to the Les-Houches accord, and uses the POWHEG...
Daniel Andreas Britzger
(Ludwig-Maximilians-Universitat Munchen)
27/03/2012, 17:50
Hadronic final states
New results on normalised inclusive jet, di-jet and trijet differential cross sections in neutral current deep-inelastic ep scattering (DIS) based on a regularised unfolding procedure are presented. Detector effects like acceptance and migrations as well as statistical correlations between the multi-jets and the inclusive DIS events are taken into account in this procedure. The DIS phase space...
ewald paul
(P)
27/03/2012, 18:10
Hadronic final states
Differential inclusive-jet cross sections have been measured in photoproduction for boson virtualities Q2 < 1 GeV2 with the ZEUS detector at HERA using an integrated luminosity of 300 pb-1.
Jets were identified in the laboratory using the kt cluster algorithm in the longitudinally inclusive mode. Cross sections are presented as functions of the jet pseudorapidity, etajet,and the jet...
Sara Collins
(University of Regensburg)
28/03/2012, 08:30
Spin physics
Flavour singlet contributions to the nucleon spin are elusive due to
the fact that they cannot be determined directly in experiment but
require extrapolations to the small x region. Direct calculations of
these contributions are possible using Lattice QCD, however, they pose
a significant computational challenge due to the presence of
disconnected quark line diagrams. I report on...
Albert Bursche
(University of Zurich),
Albert Bursche
(Universitaet Zuerich (CH))
28/03/2012, 08:30
Hadronic final states/diffraction and vector mesons
Johannes Bluemlein
(DESY, Zeuthen)
28/03/2012, 08:30
Heavy flavours/structure functions
We report on recent results obtained for the massive Wilson coefficients which contribute to the structure function $F_2(x,Q2)$ at $O(\alpha_s2)$ and $O(\alpha_s3)$ in the region $Q2/m2 \gsim 10$ for general values of
the Mellin variable $N$ as well as to corresponding operator matrix elements emerging in FVNSs.
Dr
Kieran Boyle
(RIKEN BNL Research Center)
28/03/2012, 08:30
Future of DIS
During 12 years of operations, PHENIX has measured the gluon helicity structure of the proton, probed the proton transverse spin structure, studied effects in cold nuclear matter, discovered a strongly coupled QGP and has studied many of its basic properties. In parallel with ongoing luminosity upgrades at RHIC, PHENIX is in the process of planning and commissioning a series of upgrades in...
Mr
Felix Bruemmer
(Heidelberg University)
28/03/2012, 08:30
Electroweak and searches
The LHC is closing in on the Minimal Supersymmetric Standard Model. The null results from superparticle searches, and the preliminary
evidence for a 124-126 GeV Higgs, severely constrain various popular minimal scenarios. In this talk I will review these constraints,
and point out how the LHC results can still be accommodated within the MSSM. The resulting superparticle mass spectra may...
Saeid Paktinat Mehdiabadi
(School of Particles and Accelerator Inst. for Res. in Fundam. S)
28/03/2012, 08:48
Electroweak and searches
We present results of searches for SUSY production at CMS in events
containing hadronic jets and missing energy. Various discriminants
based on the event kinematics are employed to suppress standard-model
backgrounds. The results are interpreted in the context of the Constrained
Minimal Supersymmetric Standard Model, and of a number of "simplified
models.
Fred Olness
(Southern Methodist University)
28/03/2012, 08:50
Heavy flavours/structure functions
We analyze the properties of the ACOT scheme for heavy quark
production and make use of the MS-bar massless results at NNLO and
N3LO for the structure functions F2 and FL in neutral current
deep-inelastic scattering to estimate the higher order corrections.
For this purpose we decouple the heavy quark mass entering the phase
space from the one entering the dynamics of the short distance...
Hamlet Zohrabian
28/03/2012, 08:50
Hadronic final states/diffraction and vector mesons
The production of photons at very small angles with respect to the proton
beam direction is studied in deep-inelastic positron-proton scattering at
HERA. The data are taken with the H1 detector in the years 2006 and 2007
and correspond to an integrated luminosity of $126 \mathrm{pb}^{-1}$. The
analysis covers the range of negative four momentum transfer squared at the
positron vertex...
Mayya Golembiovskaya
(DESY)
28/03/2012, 09:05
Spin physics
The HERMES experiment at DESY, Hamburg collected a set of data on hard exclusive vector meson (rho,phi,omega) leptoproduction using the 27.6 GeV self-polarized lepton beam of HERA accelerator and longitudinally or transversely polarized or unpolarized gas target. The latest results on spin density matrix elements of exclusive phi meson production using the full statistics collected at HERMES,...
Martin Niegel
(KIT - Karlsruhe Institute of Technology (DE))
28/03/2012, 09:06
Electroweak and searches
We present results of searches for SUSY production at CMS in
events with lepton signatures. These include final states with
single isolated leptons, Z bosons decaying to lepton pairs, non-resonant
same- and opposite-sign lepton pairs, and three or more isolated leptons.
The results are used to exclude previously unexplored regions of the
supersymmetric parameter space assuming R-parity...
Lidia Goerlich
(High Energy Department-Henryk Niewodniczanski Inst. Nucl. Physic)
28/03/2012, 09:10
Hadronic final states/diffraction and vector mesons
Deep-inelastic positron-proton scattering events at low photon virtuality Q^2 with a forward jet, produced at small angles with respect to the proton beam, are measured with the H1 detector at HERA. A subsample of events with an additional jet in the central region is also studied. For both samples differential cross sections and normalised distributions are measured as a function of the...
Sven-Olaf Moch
(DESY, Zeuthen)
28/03/2012, 09:10
Heavy flavours/structure functions
We present exact results for the heavy-quark structure functions in deep-inelastic scattering (DIS) in different kinematical regimes and to next-to-next-to-leading order (NNLO) in perturbative QCD.
We combine the behavior near threshold, in the high-energy limit and at asymptotically large $Q2 \gg m2$ to derive approximate expressions at NNLO accuracy.
The remaining theoretical uncertainties...
Vadim Ptitsyn
(B)
28/03/2012, 09:20
Future of DIS
The accelerator design of future high-energy high-luminosity electron-hadron collider at RHIC called eRHIC is presented. We plan adding energy recovery linacs to accelerate the electron beam to 20 (potentially 30) GeV and to collide the electrons with hadrons in RHIC. The center-of-mass energy of eRHIC will range from 30 to 200 GeV. The luminosity exceeding 10^34 cm^-2 s^-1 can be achieved in...
Carsten Peter Meyer
(Johannes-Gutenberg-Universitaet Mainz (DE))
28/03/2012, 09:24
Electroweak and searches
Searches for supersymmetry at the LHC also embrace signatures from R-parity violating processes. These can be final states with resonant or non-resonant lepton flavour violation or multiple leptons. The talk presents recent results from searches for R-partity violation in events containing leptons based on data recorded in 2011 by the ATLAS detector.
Francesco Hautmann
(University of Oxford (GB))
28/03/2012, 09:30
Hadronic final states/diffraction and vector mesons
We discuss QCD aspects of forward jet hadroproduction, including issues on factorization at large rapidities; shower Monte Carlo implementations; the role of forward jet and energy flow measurements at the LHC to investigate contributions to parton showers from large-angle gluon radiation and from multiple parton interactions.
Mr
Martin Leitgab
(University of Illinois at Urbana-Champaign)
28/03/2012, 09:30
Spin physics
Fragmentation functions (FFs) describe the formation of final state particles from a partonic initial state. Precise knowledge of these functions is a key ingredient in accessing quantities such as the nucleon spin structure in semi-inclusive deep inelastic scattering and proton proton collisions. However, fragmentation functions can currently not be determined from first principles Quantum...
Isabella Bierenbaum
(University Hamburg)
28/03/2012, 09:30
Heavy flavours/structure functions
I report on the calculation of the one-loop correction to the soft-gluon current with massive fermions. This current is process independent and controls the singular behavior of one-loop massive QCD amplitudes in the limit when one external gluon becomes soft. It therefore constitutes a necessary ingredient for the numerical evaluation of observables with massive fermions at hadron colliders...
Federica Legger
(Ludwig-Maximilians-Univ. Muenchen)
28/03/2012, 09:42
Electroweak and searches
Searches for supersymmetric squarks and gluinos in events containing jets, missing transverse momentum with or without leptons are presented. The results are based on the full data sample (5 fb-1) recorded in 2011 at sqrt(s)=7 TeV cebtre-of-mass energy by the ATLAS experiment at the LHC.
Simone Marzani
(IPPP / Durham University)
28/03/2012, 09:50
Hadronic final states/diffraction and vector mesons
I discuss jet vetoes as a means of probing colour flow in hard scattering processes in hadronic collisions. As an example, I describe a calculation of the dijet cross-section with a jet veto which resums the leading logarithms of the veto scale and it is matched to a fixed-order computation.
I compare this prediction to the measurement performed by the ATLAS collaboration as well as to other...
José Daniel Madrigal
(IFT UAM/CSIC, Madrid)
28/03/2012, 10:30
Hadronic final states/diffraction and vector mesons
Perturbative N=4 SYM computations for dijet production within the BFKL regime are shown to approach closely QCD predictions for suitable observables sensitive to the Möbius invariance of Regge limit. This similarity is strengthened by an appropriate choice of renormalization scale.
Cynthia Keppel
(Hampton University)
28/03/2012, 10:30
Andrii Gizhko
(Kiev University + DESY)
28/03/2012, 10:30
Heavy flavours/structure functions
Charm production has been measured with the ZEUS detector
in deep inelastic ep scattering at HERA.
The measurement is based on the full reconstruction of the decay chain
D*->D0pis, D0->Kpi and exploits the full HERA II statistics.
Differential cross sections have been measured.
The kinematic range is 1.5 GeV < pT(D*) < 10GeV, |eta(D*)| < 1.5,
5 < Q2 < 1000GeV2 and 0.02 < y <...
Paolo Lodone
(Scuola Normale Superiore of Pisa)
28/03/2012, 10:30
Electroweak and searches
We review the status of motivated beyond-MSSM scenarios in the light of the first searches at the LHC. In particular, we discuss the consequences for model building of a Higgs boson at about 125 GeV and of taking seriously the excess in the direct CP violation in the charm sector.
Dr
Jian-Wei Qiu
(Brookhaven National Lab)
28/03/2012, 10:30
Spin physics
Large transverse single spin asymmetries (SSAs) of cross sections with a large momentum transfer in high energy collisions were once thought impossible in QCD. With over 30 years of experimental as well as theoretical efforts, large SSAs are not only possible in QCD, but also carry extremely valuable information on the motion and structure of quarks and gluons inside a polarized hadron. In...
Vladislav Libov
(DESY)
28/03/2012, 10:48
Heavy flavours/structure functions
Charm production in deep inelastic scattering has been measured with
the ZEUS detector using the full HERA II data set. The charm content in events with a jet has been extracted using the decay length significance and invariant mass of secondary vertices. Differential cross sections as a function of Q2, Bjoerken x, ET(jet) and eta(jet) were measured and compared to theoretical predictions....
Carlos Chavez Barajas
(CERN)
28/03/2012, 10:48
Electroweak and searches
Supersymmetry with large mixing between left and right scalar fermions predicts that the lightest partners of the SM fermions belong to the third generation. Moreover, naturalness arguments favour stop masses not too far from that of the top quark. The talk presents results from searches for gluino mediated sbottom and stop production, direct sbottom production, and gluino and squark mediated...
David Zaslavsky
(Penn State University)
28/03/2012, 10:50
Hadronic final states/diffraction and vector mesons
We investigate the effects of the saturation boundary on small-x evolution at the next-to-leading order accuracy and beyond. We demonstrate that the instabilities of the next-to-leading order BFKL evolution are not cured by the presence of the nonlinear saturation effects, and a resummation of the higher order corrections is therefore needed for the nonlinear evolution. The renormalization...
Dr
Matthew Lamont
(BNL)
28/03/2012, 10:55
Future of DIS
The STAR experiment is one of the flagship experiments at the Relativistic Heavy-Ion
Collider at Brookhaven Lab. Since starting to take data at the turn of the century, STAR’s
large acceptance and measurement capabilities have proved to be vital in terms of
characterising the QGP soup produced in heavy-ion collisions and heading towards a
measurement of the proton spin in polarised p+p...
Dr
Yousef Makdisi
(Brookhaven National Laboratory)
28/03/2012, 11:05
Spin physics
Utilizing the RHIC polarized proton collider with transverse spin the PHENIX detector carried out cross section and asymmetry measurements in inclusive pizero and eta production at mid rapidity |n| < 0.35 using the central EM calorimeters where vanishing asymmetries were found. However, significant pizero and eta asymmetries were measured in the forward rapidity 3.1 < n < 3.9 using the MPC...
Eva Hennekemper
(Uni Heidelberg)
28/03/2012, 11:06
Heavy flavours/structure functions
Inclusive production of D* mesons in deep-inelastic ep scattering at HERA is studied in the range 5 < Q^2 <100 GeV^2 of the photon virtuality and 0.02 < y < 0.7 of the inelasticity of the scattering process. The observed phase space for the D* meson is p_T(D*) > 1.25 GeV and |eta(D*)| < 1.8. The data sample corresponds to an integrated luminosity of 348 pb^{-1} collected with the H1 detector....
Louise Heelan
(University of Texas at Arlington (US))
28/03/2012, 11:06
Electroweak and searches
Naturalness arguments for weak-scale supersymmetry favour supersymmetric partners of the Higgs and electroweak gauge bosons, so-called gauginos, with masses not too far from those of their Standard Model counterparts. Gauginos with masses less than a few hundred GeV can give rise to direct pair production rates at the LHC that can be observed in the data sample recorded in 2011 by the ATLAS...
Dr
Martin Hentschinski
(IFT UAM/CSIC Madrid)
28/03/2012, 11:10
Hadronic final states/diffraction and vector mesons
We report on recent progress in the evaluation of next-to-leading order (NLO) corrections to forward-backward jet observables, using Lipatov's QCD high energy effective action. We calculate both real and virtual corrections to the quark induced forward jet vertex at NLO, making use of a new regularization method and a subtraction mechanism. We also present the real NLO corrections to the...
Dongwook Jang
(Carnegie-Mellon University (US))
28/03/2012, 11:24
Electroweak and searches
We present results of searches for SUSY production at CMS in
events with one or two isolated photons. The results are interpreted
in terms of gauge-mediation models, with the gravitino as the
lightest supersymmetric particle.
David d'Enterria
(CERN)
28/03/2012, 11:30
Structure functions
The impact of isolated-photon data from proton-(anti)proton collisions at RHIC, SppbarS, Tevatron and LHC energies, on the parton distribution functions of the proton is studied using a recently developed Bayesian reweighting method. The impact on the gluon density of the 35 existing isolated-gamma measurements is quantified using next-to-leading order (NLO) perturbative QCD calculations...
Susan Cheatham
(McGill University (CA))
28/03/2012, 11:30
Heavy flavours
The production of Quarkonium is an important testing ground for QCD calculations. The J/
psi and Upsilon production cross-sections are measured in proton-proton collisions at the
ATLAS detector. Differential cross sections as a function of transverse momentum and
pseudorapidity will be presented. The fraction of J/\psi produced in $B$-hadron decays are
also measured and the differential...
Andreas Vogt
(University of Liverpool)
28/03/2012, 11:30
Hadronic final states/diffraction and vector mesons
Recently a method has been developed to extend the resummation of large-x double logarithms in inclusive DIS and semi-inclusive e^+e^- annihilation (SIA) to terms and quantities not addressed by the soft-gluon exponentiation. The N^nLL (leading log, next-to-leading log etc) resummation is based on N^nLO fixed-order results, the large-x structure of DIS and SIA in dimensional regularization and...
Vincent Sulkosky
(MIT)
28/03/2012, 11:30
Spin physics
Jefferson Lab experiment E06-010 measured the target-single spin (SSA)
and double spin asymmetries (DSA) in semi-inclusive deep inelastic pion electroproduction on a transversely polarized He-3 target. The
measured asymmetry (A_UT) is sensitive to the nucleon transversity and
Sivers distribution functions, whereas the measured A_LT asymmetry is
related to the transverse momentum...
Alexis Kalogeropoulos
(Inter-University Institute for High Energies (BE))
28/03/2012, 11:42
Electroweak and searches
We present results of searches for SUSY production at CMS in events
containing hadronic jets and missing energy. The tagging of heavy
flavor in the jets is used both to distinguish standard-model
components, and for sensitivity to those SUSY models that lead to
final states rich in heavy-flavored particles.
Daniele Fasanella
(Universita e INFN (IT)),
Daniele Fasanella
(INFN)
28/03/2012, 11:48
Heavy flavours
Abstract missing
Voica Ana Maria Radescu
(Deutsches Elektronen-Synchrotron (DE))
28/03/2012, 11:50
Structure functions
HERAFitter, a common initiative of the H1 and ZEUS collaborations, is an open source software package which provides a framework for precision QCD analyses, based on the evolution package of QCDNUM. The beta-release of the HERAFItter package contains a set of programs to fit inclusive deep inelastic scattering cross section data from HERA as well as Drell-Yan and inclusive jet processes, which...
Markus Diehl
(DESY)
28/03/2012, 13:30
Diffraction and vector mesons/spin physics
The spatial distribution of partons in the proton or a nucleus can be
probed in suitable exclusive scattering processes. I review the
theoretical foundation and the physics interest of this idea, and I report on recent performance estimates for parton imaging in the proton at an Electron-Ion collider.
Ferenc Sikler
(Hungarian Academy of Sciences (HU))
28/03/2012, 13:30
Hadronic final states
Inclusive hadron production (multiplicities and spectra) in p-p
collisions in CMS
Prof.
Bernd Kniehl
(Univ. Hamburg)
28/03/2012, 13:30
Heavy flavours
We study the polarization observables of $J/\psi$ hadroproduction
at NLO in NRQCD, including the $^3\!P_J^{[8]}$ channel.
Exploiting the color-octet long-distance matrix elements previously extracted through a global fit to unpolarized $J/\psi$ production
data, we provide theoretical predictions in the helicity and Collins-Soper frames and compare them with data from CDF and ALICE.
The...
Gennaro Corcella
28/03/2012, 13:30
Electroweak and searches/structure functions
Searching for heavy neutral gauge bosons Z', predicted in extensions of the Standard Model based on a U(1)' gauge symmetry, is among the main new physics investigations undertaken by the experiments at the Tevatron and at the Large Hadron Collider.
I will discuss study Z' phenomenology at hadron colliders according to several U(1)'-based models and in the Sequential Standard Model. In...
Ionut Cristian Arsene
(GSI - Helmholtzzentrum fur Schwerionenforschung GmbH (DE))
28/03/2012, 13:48
Heavy flavours
Due to their large mass, heavy quark pairs are considered to be produced in the first instants
of the collision in hard scatterings of partons which can be described perturbatively. However, the bound states of these pairs
are produced via soft non-perturbative processes. The interplay between the perturbative and
non-perturbative processes involved in quarkonium production makes this...
Hugh Skottowe
(Harvard University (US))
28/03/2012, 13:48
Electroweak and searches/structure functions
Diboson cross sections have been measure for all combinations of W,Z and isolated photons. The cross
sections are measured in kinematic regions defined by the decay kinematics, in some cases
including vetoes on additional jets. The measurements are also extrapolated to the full phase space using
theoretical calculations of the acceptance, and are additionally used to place contsraints...
Markward Britsch
(Max-Planck-Gesellschaft (DE))
28/03/2012, 13:50
Hadronic final states
Due to its unique pseudorapidity coverage and the possibility of providing measurements at low transverse momenta, the LHCb detector allows unique insight into particle production in the forward region at the LHC. The latest LHCb soft-QCD results, the measurements of charged particle multiplicity at 7 TeV and the measurement of the p/p, K-/K+, π-/π+, (p+p)/(π-+π+), (K-+K+)/( π-+π+ )...
Hervé MOUTARDE
(I)
28/03/2012, 13:55
Diffraction and vector mesons/spin physics
We present some recent results on the analysis of hard scattering processes in the framework of Generalized Parton Distributions. In particular we compute DVCS observables on unpolarized targets with the Kroll - Goloskokov model (suited to DVMP analysis). We also discuss NLO contributions to DVCS and TCS processes for various kinematic settings (collider and fixed target experiments).
Santiago Folgueras
(Universidad de Oviedo (ES))
28/03/2012, 14:06
Electroweak and searches/structure functions
We present studies of diboson production in pp collisions at
7 TeV center-of-mass energy based on data recorded by the CMS
detector at the LHC in 2010 and 2011. These include precise
measurements of W and Z production in association with a photon
and of WW production, WZ and ZZ productions at the LHC. The leptonic
decay modes of the W and Z bosons are used. The results are
interpreted in...
Mr
Akihisa Takahara
(CNS, University of Tokyo and JRA RIKEN)
28/03/2012, 14:06
Heavy flavours
Title:J/psi Photoproduction in ultra-peripheral Au+Au collisions measured by RHIC-PHENIX.
Ultra-peripheral collisions are heavy-ion collisions with impact parameter larger than twice the nuclear radius.
Since there is no nuclear overlap, strong interactions cannot occur and
ions interact through photon-ion (coherent), photon-nucleus (incoherent), and photon photon...
Ms
Nour Makke
(Trieste UNiversity, INFN)
28/03/2012, 14:10
Hadronic final states
Fragmentation functions, which turn partons into non-perturbative hadronic bound states in hard-scattering reactions, play a very important role in our understanding of the proton structure. Currently, our knowledge of fragmentation functions originates mainly from existing global QCD analyses which are mostly based on inclusive measurements in electron-positron annihilation process. While...
Dr
Valery Lyuboshitz
(Joint Institute for Nuclear Research, Dubna, Russia)
28/03/2012, 14:15
Diffraction and vector mesons/spin physics
The structure of the nucleon charge-exchange process
n + p --> p + n is investigated basing on the isotopic
invariance of the nucleon-nucleon scattering. Using the operator
of permutation of the spin projections of the neutron and proton,
the connection between the spin matrices, describing the amplitude
of the nucleon charge-exchange process at zero angle and the
amplitude of...
Manuel Kambeitz
28/03/2012, 14:24
Heavy flavours
We report recent studies on heavy flavor production in 1.96 TeV proton-antiproton collisions
collected by the CDF detector. These include a new measurement of the spin-alignment of Y mesons using dimuon decays in 6.7 fb^-1
of data. This measurement is the first to report the full angular distributions of dimuons
as functions of Y transverse momentum in both the Collins–Soper and s–channel...
Mika Vesterinen
(University of Manchester)
28/03/2012, 14:24
Electroweak and searches/structure functions
WZ/WW at the Tevatron (including WW/WZ+jets)
Mr
Gevorg Karyan
(A.I. Alikhanyan National Science Laboratory)
28/03/2012, 14:30
Hadronic final states
Hadron multiplicity ratios in semi-inclusive deep-inelastic scattering have been measured on neon, krypton and xenon targets relative to deuterium using the 27.6 GeV beam of HERA at the HERMES experiment. They are presented for pions (π+, π-), kaons (K+, K-), protons and anti-protons as a function of the virtual photon energy ν, its virtuality Q2, the fractional hadron energy z and the...
Morgan Murray
(U)
28/03/2012, 14:35
Diffraction and vector mesons/spin physics
Deeply Virtual Compton Scattering represents the best experimental channel
through which to understand Generalised Parton Distributions. The HERMES
experiment measured the most diverse set of DVCS results of any experiment;
this talk discusses the most recent sets of DVCS results released by HERMES
and the unique experimental conditions found at HERMES that facilitated the
measurements....
Klaus Dehmelt
(Stony Brook University USA)
28/03/2012, 14:40
Future of DIS
eRHIC is a proposed high luminosity, polarized Electron Ion Collider (EIC), which would make use of the existing RHIC infrastructure. eRHIC is a triple IP collider, with the possibility of using the two existing, but upgraded IP detectors and a dedicated eRHIC detector.
A detector has to be designed that can make use of present knowledge and experience gained from the HERA detectors, but has...
Giovanni Sabatino
(Universita degli Studi di Roma Tor Vergata (IT))
28/03/2012, 14:42
Heavy flavours
Studies of quarkonia production in the forward region provide important tests of NRQCD. During 2010 and 2011 the LHCb experiment has collected a dataset corresponding to an integrated luminosity of 1 fb-1 in proton-proton collisions at sqrt(s)= 7 TeV. We present studies based on 40 to 1000 fb-1 of data, including the production of the J/psi, psi(2S), Chi_c charmonium together with Upsilon...
Tom Riddick
28/03/2012, 14:42
Electroweak and searches/structure functions
The CDF collaboration has analyzed 2.2 fb-1 of Run II electron and muon data for a new precise determination of the mass of the W boson. The result is 80.387 +/- 0.019 GeV/c2, which is more precise than the combination of all preceding measurements. An update from D0 is also expected.
Iris Abt
(Werner-Heisenberg-Institut)
28/03/2012, 14:50
Hadronic final states
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....
Dr
Daria Sokhan
(in2p3)
28/03/2012, 14:55
Diffraction and vector mesons/spin physics
Generalised Parton Distributions (GPDs) offer an insight into the three-dimensional structure of the nucleon and its
internal dynamics, relating the transverse position of quarks to their longitudinal momentum. Two effective means of
accessing GPDs are Deeply Virtual Compton Scattering (DVCS) and Meson Production (DVMP), in which a high energy electron
scatters from a single quark in the...
Jolanta Brodzicka
(INP Krakow)
28/03/2012, 15:00
Heavy flavours
We present recent results on charmonium and charmonium-like states
studied by the Belle experiment at the KEK-B e+e- collider.
After years of interesting discoveries in the field of hadron
spectroscopy, Belle continues the research by measuring new final
states produced in various processes accessible at the B-Factories.
Main motivation is to complete the spectrum of charmonia...
Takuya Nobe
(Tokyo Institute of Technology (JP))
28/03/2012, 15:00
Electroweak and searches/structure functions
A search for events ep-> ep Z0 has been performed in ep collisions
at HERA using the ZEUS detector. The search is based on the entire HERA-I and HERA-II data set, amounting to 0.49 fb-1 of integrated luminosity. The Z0 was searched in the di-jet decay mode with elastic condition defined by etamax < 3, where etamax is defined as the pseudorapidity of the energy deposit in the calorimeter...
Alexander Bazilevsky
(B)
28/03/2012, 15:05
Future of DIS
Addition of a high intensity polarized electron beam facility which could realize Deep Inelastic Scattering (DIS) research with one of the RHIC beams is one of the future upgrades to the Relativistic Heavy Ion Collider (RHIC) presently under consideration. To take a full advantage of such machine evolution, after more than a decade of exciting physics results, both with heavy ion and polarized...
Dr
Valery Lyuboshitz
(Joint Institute for Nuclear Research, Dubna, Russia)
28/03/2012, 15:10
Hadronic final states
The phenomenological structure of inclusive cross sections of the
production of two neutral K mesons in hadron-hadron, hadron-nucleus and nucleus-nucleus collisions is investigated taking into account the strangeness conservation in strong and electromagnetic
interactions. Relations describing the dependence of the correlations of two short-lived and two long-lived neutral kaons
$K^0_S...
Heiner Wollny
(CEA - Centre d'Etudes de Saclay (FR))
28/03/2012, 15:15
Diffraction and vector mesons/spin physics
New results for the transverse target spin azimuthal asymmetry
$A_{UT}^{\sin(\phi-\phi_S})$ for hard exclusive $\rho^0$-meson production on a transversely polarised NH$_3$ target will be presented. The measurement was performed in 2007 and 2010 with the COMPASS detector using the 160\,GeV/$c$ muon beam of the SPS at CERN. The asymmetry is sensitive to the nucleon helicity-flip generalised...
Elisa Fioravanti
(INFN Ferrara)
28/03/2012, 15:18
Heavy flavours
Charmonium and charmonium-like states are a unique system for studying QCD and possibly exotic bound states. We present new results on such states, which are created in two-photon fusion or in electron-positron collisions and decaying into a variety of final states, including psi pi pi, eta_c pi pi, and J/psi omega.
Umberto Tamponi
(Torino)
28/03/2012, 16:00
Heavy flavours
The Belle collaboration recently reported the discovery of the p-wave
Bottomonium singlets, hb(1P) and hb(2P), the surprising observation of
resonant substructure in Y(5S) --> pi+pi-Y(nS), hb(mP) (n=1-3, m=1,2), and the first observation of the radiative transition hb(1P) --> gamma
etab(1S) in 121.4 1/fb of data collected near the Upsilon(5S) resonance
at the KEKB asymmetric-energy e^+e^-...
Jacek Ciborowski
(University of Warsaw)
28/03/2012, 16:00
Diffraction and vector mesons
The exclusive photoproduction reaction gamma p -> Upsilon(1S) p has been studied with the ZEUS detector in ep collisions
at HERA using an integrated luminosity of 468pb-1.
The measurement covers the kinematic range 60 < W < 220 GeV and
Q2 < 1 GeV2, where W is the photon--proton centre-of-mass energy
and Q2 is the photon virtuality. The exponential slope, b, of the t dependence of the...
Dr
Feng Yuan
(Lawrence Berkeley National Laboratory)
28/03/2012, 16:00
Spin physics
In this talk, we will summarize recent developments on the orbital angular momentum of partons in nucleon, from various observables in high energy processes, including generalized parton distributions, transverse momentum dependent parton distributions, etc.
Adam Robert Davison
(University College London (UK))
28/03/2012, 16:00
Hadronic final states
The internal structure of jets produced in proton-proton collisions at 7 TeV centre-of-mass energy
provides a direct test of QCD calculations of gluon and quark radiation, as well as having sensitivity
to hadronisation and underlying event. The transverse energy distribution around the jet core has been measured,
as well as the fragmentation of a jet into charged particles. Jet shapes -...
Martin Hentschinski
(Autonoma University Madrid/CSIC)
28/03/2012, 16:00
Electroweak and searches/structure functions
We study W/Z/DY + jet events where the W/Z/DY boson is produced in the forward direction of one of the colliding protons and a jet is produced in the forward direction of the second proton. The resulting large rapidity difference between the final states then opens up the phase space for BFKL evolution which we would like to study in more detail. As a by-product of our study, we also provide...
Claus Buszello
(Uppsala University (SE)),
Claus Buszello
(Department of Physics and Astronomy-University of Uppsala),
Claus Buszello
(Uppsala University)
28/03/2012, 16:18
Heavy flavours
Using the 1.3 fb$^{-1}$ sample of D0 RunII data taken between 2002 and 2006, we observe a new state decaying into $\Upsilon(1S) + \gamma$, where the $\Upsilon(1S)$ is detected by its decay into an oppositely charged muon pair, and the photon is reconstructed by its conversion into an electron-positron pair. The significance of this structure is six standard deviations and its mass is...
Jean-Baptiste Sauvan
(Universite de Paris-Sud 11 (FR))
28/03/2012, 16:18
Electroweak and searches/structure functions
W and Z boson production have been measured in the electron, muon and tau decay channels.
Total and differential cross sections, defined in terms of the decay lepton kinematics,
have been measured as a function of rapidity and transverse momentum. Ratios of the cross
sections demonstrate sensitivity to lepton universality, and the kinematic distributions
constrain parton densities and QCD...
Dr
Justyna Tomaszewska
(DESY)
28/03/2012, 16:20
Diffraction and vector mesons
The exclusive electroproduction of two pions in the mass range
0.4 < M(pipi) < 2.5 GeV has been studied with the ZEUS
detector at HERA using an integrated luminosity of
82 pb-1. The analysis was carried out in the kinematic range of
2 < Q2 < 80 GeV2, 32 < W <180 GeV and |t|<0.6 GeV,
where Q2 is the photon virtuality, W is the
photon-proton centre-of-mass energy and t is the...
Simone Marzani
(IPPP Durham)
28/03/2012, 16:20
Hadronic final states
We study the jet-mass distribution for jets produced in hadron-hadron collision in QCD. In order to obtain reliable phenomenological results we resum to all-order in perturbation theory those contributions coming from collinear and soft gluons. Beyond the leading-logarithmic accuracy the resummation is made more complicated by the presence of non-global logarithms and logarithms related to the...
Alessandro Bacchetta
(University of Pavia)
28/03/2012, 16:30
Spin physics
The determination of quark angular momentum requires the knowledge of the generalized parton distribution E in the forward limit. We assume a connection between this function and the Sivers transverse-momentum distribution, based on model calculations and theoretical considerations. Using this assumption, we show that it is possible to fit at the same time nucleon magnetic moments and...
Dr
Zhenwei Yang
(Tsinghua University (CN))
28/03/2012, 16:36
Heavy flavours
During the year 2011, the LHCb experiment has accumulated 1 fb-1 of data in proton-proton collisions data at 7 TeV, collecting a sample rich in both Bc mesons and b baryons. Studies of these states provide a wealth of new measurements as well as probes of QCD theory predictions. We will present studies of Bc production together with precision measurements of both the mass and lifetime, in...
Mr
Stephen Farry
(University College Dublin (IE))
28/03/2012, 16:36
Electroweak and searches/structure functions
We report on measurements of W and Z production in the forward region, using data collected at the LHCb experiment with a centre of mass energy of $\sqrt{s}=7$~TeV with an integrated luminosity of up to 1 fb-1. W and Z bosons are reconstructed in leptonic decay channels, and their cross-sections determined using data-driven techniques. Results are presented inclusively (within the fiducial...
Prof.
Ruben Sandapen
(University of Moncton (Canada))
28/03/2012, 16:40
Diffraction and vector mesons
We obtain a very good description of the current HERA data on diffractive rho electroproduction using a holographic
light-cone wavefunction for the rho meson. This holographic wavefunction is obtained using the Brodsky and de Teramond
correspondance between hadronic modes in AdS space and light-cone wavefunctions in physical spacetime. We also show the
corresponding holographic Distribution...
Zhao Li
(Michigan State University)
28/03/2012, 16:40
Hadronic final states
Jet Substructure at Hadron Colliders
Mariaelena Boglione
(University of Turin)
28/03/2012, 16:50
Spin physics
Following the TMD evolution scheme recently proposed for the Sivers distribution function, we propose a simple strategy to take into account this TMD Q^2 dependence in our phenomenological extraction of the Sivers function from SIDIS data. New results are presented and possible future applications are discussed.
Marco Musich
(INFN Torino (IT))
28/03/2012, 16:54
Electroweak and searches/structure functions
The mechanism of production of heavy-flavoured mesons, containing b
or c quarks, in association with vector bosons, W or Z, in the Standard
Model is only partially understood. The study of events with one or
two well-identified and isolated leptons accompanied by b-jets or
secondary vertices is therefore crucial to refine the theoretical
calculations in perturbative QCD, as well as...
Enrique Camacho Perez
(Centro Invest. Estudios Avanz. IPN (MX))
28/03/2012, 16:54
Heavy flavours
Merged abstract:
"Analysis of the decay $B_s^0 \rightarrow J/\psi K^+ K^-$ $M(K^+K^-)>1.35$~GeV"
"Measurement of the $\Lambda_b$ lifetime in the $\Lambda_b \to J/\psi \Lambda$ exclusive decay channel using the full D0 dataset"
道久 竹内
(Heidelberg)
28/03/2012, 17:00
Hadronic final states
Top momentum reconstruction often plays an important role for new physics signal reconstruction at the LHC. In principle for a hadronically decaying top, it is possible to reconstruct its momentum fully but one suffers from large QCD and combinatorial backgrounds.
Starting from geometrically large sizes of jets and looking into their substructure, we can efficiently reduce these background....
Prof.
Kazuhiro Tanaka
(Juntendo University)
28/03/2012, 17:00
Diffraction and vector mesons
In the conventional b_* model for the Collins–Soper–Sterman resummation,
the resummed form factor is accompanied by the nonperturbative gaussian form factor, and
it is known that the nonperturbative parameter associated with the latter exhibits the strong dependence on the logarithm of
the vector boson invariant mass.
On the other hand, an another approach to treat the impact parameter (b...
Dr
Asmita Mukherjee
(IIT Bombay)
28/03/2012, 17:10
Spin physics
We discuss the possibility of using electroproduction of $J/\psi $ as a probe of gluon Sivers function
by measuring single spin asymmetry in experiments with transversely polarized protons and electron beams.
We estimate SSA for JLab, HERMES, COMPASS and eRHIC energies using color evaporation
model of charmonium production and find asymmetry up to 25 $\%$ for certain
choices of model...
Marcus Ebert
(SLAC)
28/03/2012, 17:12
Heavy flavours
Decays of B mesons into final states containing baryons are much less understood than decays into mesons, and are useful for shedding light on baryon-production mechanisms and intermediate states. We report the results of recent and new studies of such decays, including B- -->Sigma_c++ pbar pi- pi-, B0bar -->Lambda_c+ pbar p pbar, and
B --> D(*) p pbar (npi). Both the total decay rates and...
Jonathan Anderson
(Universitaet Zuerich (CH))
28/03/2012, 17:12
Electroweak and searches/structure functions
We report on Drell-Yan production using data collected at the LHCb experiment with a centre of mass energy of $\sqrt{s}=7$~TeV in 2010. Drell-Yan events are selected with invariant di-muon masses $M_{\mu\mu}>10$~GeV/$c^2$. These measurements are sensitive to Bjorken-$x$ values as low as $1\times 10^{-5}$ and will provide important input to the knowledge of the parton density functions. The...
Daniel Andreas Britzger
(DESY)
29/03/2012, 09:00
Hadronic final states/structure functions
Standard methods for higher-order pQCD calculations of cross
sections in hadron-induced collisions are time-consuming.
The fastNLO project uses multi-dimensional interpolation
techniques to convert the convolutions of perturbative
coefficients with parton distribution functions and the
strong coupling into simple products. By integrating the
perturbative coefficients for a given...
Carlos Albert Salgado Lopez
(Universidade de Santiago de Compostela (ES))
29/03/2012, 09:00
Future of DIS
none
Prof.
Alessandro Papa
(University of Calabria and INFN Cosenza (Italy))
29/03/2012, 09:00
Diffraction and vector mesons
We calculate in the next-to-leading order the impact factor (vertex) for the production of a forward high-p_T jet, in the approximation of small aperture of the jet cone in the pseudorapidity-azimuthal angle plane. The final expression for the vertex turns out to be simple and easy to implement in numerical calculations.
Li Lin Yang
29/03/2012, 09:00
Electroweak and searches/heavy flavours
I present recent calculations of observables in top quark pair production at hadron colliders, including the total cross section, the invariant mass distribution, the transverse momentum and rapidity distributions, and the forward-backward asymmetry. The calculations are based on the resummation of threshold logarithms at NNLL accuracy beyond NLO.
William Bell
(Unknown),
William Hamish Bell
(Universite de Geneve (CH))
29/03/2012, 09:18
Electroweak and searches/heavy flavours
We present the result of a measurement of single top-quark production
in the t-channel at 7 TeV proton-proton collisions with the ATLAS
detector at the Large Hadron Collider. A lower limit on the CKM matrix
element |Vtb| is extracted from this measurement. The single-top quark
production in the Wt- and s-channels is also explored.
Dr
Bogdan Malaescu
(CERN)
29/03/2012, 09:20
Hadronic final states/structure functions
Inclusive jet and dijet double-differential cross sections have been measured in proton-proton
collisions at a centre-of-mass energy of 7 TeV using the ATLAS detector. The cross sections were
measured using jets clustered with the anti-kT algorithm. The measurements are performed in the jet
rapidity range |y|<4.4, covering jet transverse momenta from 20 GeV to 1.5 TeV and dijet...
Clara Salas
(IFT)
29/03/2012, 09:20
Diffraction and vector mesons
An iterative solution best suited for a Monte Carlo implementation for the non-forward BFKL equation is presented and possible applications discussed. We introduce running coupling effects in a way compatible with the bootstrap, fundamental condition for gluon reggeization and see how this naturally leads to renormalon effects in the infrared.
Jakub Wagner
(National Center for Nuclear Research)
29/03/2012, 09:20
Spin physics
Generalized Parton Distributions (GPDs) offer a new way to access the quark and gluon nucleon structure. We advocate the need to supplement the experimental study of deeply virtual Compton scattering by its crossed version, timelike Compton scattering (TCS) i.e. the exclusive photoproduction of a lepton pairs with large invariant mass. We review recent progress in this domain, in particular...
Nestor Armesto Perez
(Universidade de Santiago de Compostela (ES))
29/03/2012, 09:35
Philippe Calfayan
(Ludwig-Maximilians-Univ. Muenchen-Unknown-Unknown),
Philippe Calfayan
(Ludwig-Maximilians-Univ. Muenchen (DE))
29/03/2012, 09:36
Electroweak and searches/heavy flavours
Merged abstract:
"Searches for new physics effect involving top quarks"
"Search for t tbar Resonances in p pbar collisions with the ATLAS detector at LHC"
Pavel Ruzicka
(Acad. of Sciences of the Czech Rep. (CZ))
29/03/2012, 09:40
Diffraction and vector mesons
Transverse energy distributions and regions of low activity in proton-proton scattering events
are sensitive to soft physics, low x and diffractive processes, and have been measured in inclusive
"minimum bias" scatters as well as in dijet events at sqrt(s) = 7 TeV. In the inclusive analysis,
cross sections are measured differentially in terms of Delta eta F, the larger of the...
Ozlem Kaya
(Bogazici University (TR))
29/03/2012, 09:40
Hadronic final states/structure functions
Merged abstract:
"Dijet and Inclusive jet cross section measurements with CMS"
"Three jet event properties with the CMS experiment"
A. L. Kataev
(Institute for Nuclear Research of the Russian Academy of Sciences, Moscow, Russia)
29/03/2012, 09:50
Spin physics
Using operator-product expansion approach for the triangle
diagram of Axial-Vector-Vector currents symmetry I derive the singlet variant of the
Crewther
relation, which is valid in the conformal -invariant limit
of perturbative approach. I demonstrate that in the conformal-invariant
limit of U(1)-model the non-singlet coefficient function of Bjorken and Ellis-Jaffe sum
rule identically...
Victor Eduardo Bazterra
(University of Illinois at Chicago (US))
29/03/2012, 09:54
Electroweak and searches/heavy flavours
Several searches of physics beyond the standard model involving top
quarks in the final state are presented. These searches encompass top
decays in FCNC channels, resonances decaying in ttbar final states,
new heavy quarks decaying to top quarks, production of same-sign
quarks, and recent tests of various new physics models.
Andreas Vogt
(University of Liverpool)
29/03/2012, 10:00
Hadronic final states/structure functions
We present the third-order (NNLO) contributions to the timelike splitting functions governing the evolution of parton fragmentation functions in QCD. The hitherto missing quark-gluon and gluon-quark quantities have been derived by studying physical evolution kernels for photon- and Higgs-exchange DIS structure functions and their counterparts in semi-inclusive annihilation, together with...
Dr
jian zhou
(Regensburg University)
29/03/2012, 10:10
Spin physics
I will discuss the color glass condensate (CGC) based calculation of two gluon TMDs inside a large nucleus at small x. The main focus is on the linearly polarized gluon TMD which is often referred to as the gluon Boer-Mulders function. With the derived gluon TMDs at small x, it is shown that an effective TMD factorization can be established at small x in a certain kinematical region. As a...
Yvonne Peters
29/03/2012, 10:12
Electroweak and searches/heavy flavours
The kinematic properties of the data used for the measurement
of the top-antitop quark pair production and of the single top
quark production cross sections are used to set constraints on
a variety of signals of physics beyond the SM. We set constraints
on possible 4th generation top quarks, on possible resonances
that would decay into top-antitop quark pairs, on possible
resonances that...
Paolo Bolzoni
(DESY)
29/03/2012, 10:20
Hadronic final states/structure functions
We present a new approach in considering and including the perturbative and non-perturbative contributions to the gluon-quark multiplicity ratio. The new method is motivated by new developments in timelike small x resummation and exploit the recently computed NNLO timelike splitting fnctions. Comparison of our new results with other methods and with data will also be presented.
José Daniel Madrigal
(IFT UAM/CSIC, Madrid)
29/03/2012, 11:00
Diffraction and vector mesons
Lipatov's high-energy effective action is a very promising tool for computations in the Regge limit beyond leading order. Its use has been however restricted to tree-level calculations for many years. Recently a regularization/subtraction prescription was proposed that allows to extend the formalism to deal with loops in a consistent way. We illustrate the procedure with the computation of the...
Hans Jozef H Van Haevermaet
(University of Antwerp (BE))
29/03/2012, 11:00
Hadronic final states
Characterization of the underlying event in p-p collisions in CMS
Jernej Kamenik
(Jozef Stefan Institute)
29/03/2012, 11:00
Electroweak and searches/heavy flavours
Following recent intriguing experimental results on top quark pair production from the Tevatron I review the present status of new physics explanations put forward to explain the experimental observations deviating from standard model predictions. All proposals face severe constraints from precisely measured flavor, electroweak and high pt collider observables. Possible future measurements at...
Mr
Wilco den Dunnen
(VU University Amsterdam)
29/03/2012, 11:00
Spin physics
We investigate the possible role of linearly polarized gluons in Higgs production from unpolarized pp collisions. The angular independent transverse momentum distribution of the produced Higgs boson is found to exhibit a modulation (max 30%) with respect to the naive, unpolarized expectation, with the sign depending on the CP nature of the Higgs boson. The transverse momentum distribution of a...
Elisa Musto
(Universita e INFN (IT)), Dr
elisa musto
(ATLAS)
29/03/2012, 11:18
Electroweak and searches/heavy flavours
Merged abstract:
"Limit on the branching fraction for the rare B-decay Bs->mumu in ATLAS"
"Exclusive B-Decays in ATLAS"
Christopher Braun
(Friedrich-Alexander-Univ. Erlangen (DE))
29/03/2012, 11:20
Spin physics
For each quark flavour three independent parton distribution functions (PDF) are necessary to describe the nucleon at twist-two level, the quark distribution f1(x), the helicity distribution g1(x) and the transversity distribution h1(x). The transversity distribution function is chiral-odd and therefore is not accessible in deep inelastic scattering (DIS). However, h1(x) can be observed in...
Dr
Arthur Moraes
(University of Glasgow (GB))
29/03/2012, 11:20
Hadronic final states
The majority of proton-proton collisions at the LHC contain only soft, low transverse-momentum scatters. Such
scatters also occur between the remnants of the protons in conjunction with short-distance, high momentum
scatters. Measurements of soft particle production and energy flow are presented fir a wide range of different
kinematic selections; correlations between the produced...
Dr
Marat Siddikov
(UTFSM)
29/03/2012, 11:20
Diffraction and vector mesons
In this talk we present the results of the diffractive single-pion production on the protons and nuclei (both for the coherent and incoherent cases). We demonstrate that all the evaluations which are based on Adler relation (AR) are valid only in the region up to 10 GeV, in the regime of short lifetime of heavy hadronic fluctuations. At higher energies, when all the relevant time scales...
Lucia Grillo
29/03/2012, 11:36
Electroweak and searches/heavy flavours
We report recent results from indirect searches for BSM physics using flavor processes in the
whole sample of 9.6 fb^-1 collected by CDF in Tevatron Run II. These include the final measurements of flavor-changing-neutral-current, rare B-> mu^+ mu^- and B-> K mu^+ mu^- decays, the final measurements of the bottom-strange mixing phase (phi_s) using Bs->J/Psi Phi decays, measurements of the...
Dr
Jeffrey Berger
(Penn State University (USA))
29/03/2012, 11:40
Diffraction and vector mesons
In previous numerical work the solution to the BK evolution equation
with impact parameter dependence was calculated with modeled confinement effects.
This solution is used to calculate diffractive cross sections
for the vector mesons J/Psi, Rho, and Phi. In order to bring the
numerical results into agreement with HERA data modification to the
photon wavefunction is necessary. This...
Aurore Courtoy
(IFPA, AGO Dpt., Universite de Liege)
29/03/2012, 11:40
Spin physics
We report on the first extraction of interference fragmentation functions from the semi-inclusive production of two hadron pairs in back-to-back jets in $e^+e^-$ annihilation. A nonzero asymmetry in the correlation of azimuthal orientations of opposite $\pi^+\pi^-$ pairs is related to the transverse polarization of fragmenting quarks through a significant polarized dihadron fragmentation...
Dmytro Volyanskyy
(Max-Planck-Gesellschaft (DE))
29/03/2012, 11:40
Hadronic final states
We present the results on the energy flow measured with minimum-bias data collected by the LHCb experiment in $pp$ collisions at $\sqrt{s}=7$~TeV for inclusive minimum bias interactions, hard scattering processes and events with enhanced or suppressed fractions of diffractive contributions. The measurements are performed in the pseudorapidity range $2<\eta<5$ which corresponds to the main...
Dr
Marco Bomben
(LPNHE - Univ. P. et Marie Curie (Paris VI) (FR) & CNRS)
29/03/2012, 11:54
Electroweak and searches/heavy flavours
Merged abstract:
"Searches for new physics in CP-violation at BABAR"
"Lepton-number and lepton-flavor violation in B decays at BABAR"
Christian Hoeppner
(Technische Universitaet Muenchen (DE))
29/03/2012, 12:00
Spin physics
Lepton-nucleon scattering experiments are performed to investigate the (spin-)structure of nucleons. The theoretical framework for the interpretation of such measurements is perturbative QCD (pQCD). In this contribution we present the measurement of the cross section for the quasi-real photoproduction of charged hadrons with high transverse momenta in muon-deuteron scattering at COMPASS...
Anna Zsigmond
(Hungarian Academy of Sciences (HU))
29/03/2012, 12:00
Hadronic final states
Inelastic cross section measurement in p-p collisions in CMS
Dr
Krzysztof Kutak
(Instytut Fizyki Jadrowej Polskiej Akademii Nauk)
29/03/2012, 12:00
Diffraction and vector mesons
Motivated by the regime of QCD explored nowadays at LHC where both the total energy of collision and momenta transfers are high, evolution equations of high energy factorization are investigated.
Briefly we overview results obtained so far for proton proton collisions within high energy factorization approach for jet related observables and we give some predictions for proton lead. This...
Franco Simonetto
(Universita e INFN (IT))
29/03/2012, 12:12
Electroweak and searches/heavy flavours
Abstract missing
Dr
Michal Deak
(Universidade de Santiago de Compostela)
29/03/2012, 12:20
Diffraction and vector mesons
We compare two Monte Carlo implementations of resummation schemes for the description of parton evolution at small values of Bjorken x. One of them if based on the BFKL evolution equation. The other one is based on the CCFM partonic kernel where QCD coherence effects are introduced. It has been argued that both approaches agree with each other in the x to 0 limit. We show that this is not the...
Mrs
Melanie Pfeuffer
(University of Regensburg)
29/03/2012, 12:20
Spin physics
We consider the cross section for the photoproduction reaction
gamma + p -> h+ X in fixed-target scattering at COMPASS, where the hadron is produced at large transverse momentum. We investigate the role played by higher-order corrections to the cross section. In particular we adress large logarithmic ``threshold'' corrections to the partonic cross sections, which we resum to all orders.
Christian Roehr
(K)
29/03/2012, 12:20
Hadronic final states
We review the modelling of multiple interactions in the event generator
Herwig++ and study implications of recent tuning efforts to Tevatron and
LHC data. A crucial ingredient to a successful description of minimum
bias and underlying event observables is a model for colour
reconnection. Improvements to this model inspired by statistical physics
are presented.
Amanda Sarkar
(University of Oxford (GB)),
Pedro Jimenez-Delgado
(University of Zürich),
Ringaile Placakyte
(Deutsches Elektronen-Synchrotron (DE))
30/03/2012, 09:00
Paul Richard Newman
(University of Birmingham (GB)),
elke-caroline Aschenauer
(BNL)
30/03/2012, 09:40
Dimitri Colferai
(Unknown),
Marta Ruspa
(Universita e INFN (IT)),
Richard Polifka
(University of Toronto (CA))
30/03/2012, 10:50
Dr
David South
(DESY),
Hwi Dong Yoo
(Purdue University (US))
30/03/2012, 11:30
Jan-Christopher Winter,
Klaus Rabbertz
(KIT - Karlsruhe Institute of Technology (DE)),
Krzysztof Nowak
(Deutsches Elektronen-Synchrotron (DE))
30/03/2012, 13:30
Ingo Schienbein
(Universite Joseph Fourier),
Jolanta Brodzicka
(INP PAS Krakow),
Massimo Corradi
(Universita e INFN (IT))
30/03/2012, 14:10
Dr
Kresimir Kumericki
(University of Zagreb),
Marc Schlegel
(University of Tuebingen),
Sergey Yaschenko
(DESY)
30/03/2012, 15:20
Jochen Bartels
Diffraction and vector mesons
I report on a theoretical study of the Drell Yan production process in the region of very small x. Particular attention is given to the breakdown of factorization.
Boris Ermolaev
(IFMO Inst. of Fine Mechanics and Optics)
Structure functions
Abstract: We show that both the $k_T$- and collinear factorization for DIS
structure functions can be obtained by consecutive reductions of the more general factorization of the Compton scattering amplitude.
Each of these reductions an approximation valid under certain assumptions.
In particular, the transitions to the $k_T$- factorization is possible when the virtualities of the partons...
Konstantin Goulianos
(Rockefeller University (US))
Diffraction and vector mesons
New results on the recoil antiproton 4-momentum transfer distribution, t, and a search for a diffractive dip in proton-antiproton inclusive and dijet diffractive production are presented in the range 0<|t|<4 (GeV/c)2, measured by CDF II at √1.96 TeV. The results are compared with similar measurements from diffractive deep inelastic scattering experiments at HERA, diffractive pp collisions at...
Simonetta Liuti
(University of Virginia)
Spin physics
Exclusive $\pi^o$ electroproduction from nucleons was suggested in as a method
for extracting from experiment the tensor charge, transversity and other quantities related to chiral odd combinations
of generalized parton distributions.
In this contribution we explain the details of the process: {\it i)} the connection between the helicity description and the cartesian basis; {\it ii)}...
Klaus Johannes Reygers
(Ruprecht-Karls-Universitaet Heidelberg (DE))
Oliver Kortner
(Max-Planck-Institut fuer Physik (Werner-Heisenberg-Institut) (D)
Daniel De Florian
(Laboratorio de Fisica Teorica Departamento de Fisica)
