Prof.
Georg Weiglein
(Deutsches Elektronen-Synchrotron (DE))
23/07/2015, 09:00
Top and Electroweak Physics
talk
The relation between the mass of the W boson, the Z boson, the fine structure constant and the Fermi constant is one of the most important precision observables, which provides access to the quantum structure of the underlying theory and has a high sensitivity for discriminating between different models. Updated predictions for the W-boson mass in the Standard Model (SM) as well as its minimal...
Jenny Lyn Holzbauer
(Mississippi University (US))
23/07/2015, 09:25
Top and Electroweak Physics
talk
We present $W$ boson and lepton charge asymmetry measurements from $W$ decays in the electron channel, with 9.7 fb$^{-1}$ of RunII data collected by the D0 detector at the Fermilab Tevatron Collider. The electron charge asymmetry is presented as a function of the electron transverse momentum and pseudo-rapidity out to $|\eta|\leq 3.2$; we also give the $W$ charge asymmetry as a function of $W$...
Aleksandra Dimitrievska
(Institute of Physics Belgrade (RS))
23/07/2015, 09:43
Top and Electroweak Physics
talk
The ATLAS Collaboration is engaged in precision measurement of fundamental Standard Model parameters, e.g. the weak-mixing angle and the complete set of coefficients that describe the angular distributions of Drell-Yan production.
A measurement of the forward-backward asymmetry for the neutral current Drell Yan process is presented and the results are then used to extract a measurement of...
Rajdeep Mohan Chatterjee
(Tata Inst. of Fundamental Research (IN))
23/07/2015, 10:01
Top and Electroweak Physics
talk
The production of W and Z bosons is studied in pp collisions at a center-of-mass energy of 8 TeV using data collected in the CMS experiment. W events are selected containing an isolated, energetic electron or muon. Z events are selected containing a pair of isolated, energetic electrons or muons. Data-driven methods are used to estimate reconstruction and triggering efficiencies, and well as...
Aran Garcia-Bellido
(University of Rochester)
23/07/2015, 10:19
Top and Electroweak Physics
talk
We present measurements of the $Z\gamma$* rapidity and $\phi$* production distributions and the weak mixing angle from $Z$ boson decays, with all RunII data collected by the D0 detector at the Fermilab Tevatron Collider. The measurement of $\phi*$ probes the same physical effects as the $Z/\gamma$* boson transverse momentum, but is less susceptible to the effects of experimental resolution and...
William James Barter
(CERN)
23/07/2015, 11:30
Top and Electroweak Physics
talk
LHCb's unique forward acceptance allow for complementary measurements of electroweak boson production. Thanks to the precise vertex detector and the gas injection system LHCb has the most precise luminosity calibration at the LHC. New precision W and Z cross-section measurements at 7 and 8 TeV are presented.
Matthias Saimpert
(CEA/IRFU,Centre d'etude de Saclay Gif-sur-Yvette (FR))
23/07/2015, 11:48
The scheduled installation of forward proton detectors at the LHC nearby the CMS and ATLAS experiments will provide a -- somewhat surprising -- opportunity to measure the light-by-light scattering with unprecedented precision by taking advantage of the coherent photon flux emitted by the protons. The detection of the intact protons allows to reconstruct the full kinematic of the event which is...
Mariusz Przybycien
(AGH University of Science and Technology (PL))
23/07/2015, 12:06
Top and Electroweak Physics
talk
The measurement of the exclusive gamma+gamma -> ll production cross-section in proton-proton collisions at a centre-of-mass energy of 7 TeV has been carried out by the ATLAS experiment at the LHC, based on an integrated luminosity of 4.6 fb-1. The ratios to the pure QED cross-section predictions are measured in the electron and muon channels and are found to be consistentโจ with the previous...
Manfred Jeitler
(Austrian Academy of Sciences (AT))
23/07/2015, 12:24
Top and Electroweak Physics
talk
A search for exclusive or quasi-exclusive W+W- production induced by photon-photon exchange in pp collisions at sqrt(s)=8 TeV is reported using data corresponding to an integrated luminosity of 19.7/fb. Events are selected by requiring the presence of an electron-muon pair with large transverse momentum pT > 30 GeV and no associated charged particles detected from the same vertex. The observed...
Narei Lorenzo Martinez
(Indiana University (US))
23/07/2015, 12:42
Top and Electroweak Physics
talk
The ATLAS collaboration has carried a set of measurements to test self-interactions of the electroweak gauge bosons. Among these measurements are the production of W or Z bosons in the vector-boson fusion channel and two same-charge W bosons in the vector-boson scattering channel. Furthermore, the first evidence for the production of three gauge bosons has been obtained. Cross sections are...
Francesco Fabozzi
(Universita e INFN, Napoli (IT))
23/07/2015, 14:30
Top and Electroweak Physics
talk
Measurements are presented of t-channel single top quark production in proton-proton collisions at the LHC at centre-of-mass energies of 7 and 8 !TeV, using data collected with the CMS experiment during the years 2011 and 2012. The analyses consider decay channels where the W from the top decays into electron-neutrino or muon-neutrino, and makes use of kinematic characteristics of electroweak...
Mario Merola
(Universita e INFN, Napoli (IT))
23/07/2015, 14:48
Top and Electroweak Physics
talk
Measurements of single top quark production in the tW-channel in pp collisions are presented. In the tW-channel a top quark is produced in association with a W boson. The data were collected in the years 2011 and 2012 at centre-of-mass energies of 7 and 8 !TeV. The experimental signature is similar to top pair production, and there is interference at higher orders between the two processes....
Manfredi Ronzani
(Albert-Ludwigs-Universitaet Freiburg (DE))
23/07/2015, 15:06
Top and Electroweak Physics
talk
We present measurements of the cross sections for the two main
production modes of single top quarks in ppbar collisions at a center-of-mass energy of 1.96 TeV in the Run II data collected with the CDF and D0 detector at the Fermilab Tevatron Collider. For this measurement the full data set corresponding to an integrated luminosity of up to 9.7 fb$^{-1}$ per experiment is used. We report...
Reinhild Peters
(University of Manchester (GB))
23/07/2015, 15:24
Top and Electroweak Physics
talk
We present the most recent measurements of the cross section for pair
and single production of the top quark with the D0 detector at the
Tevatron proton-antiproton collider. Measurements use the full D0
Run II data corresponding to an integrated luminosity of 9.7 fb^-1.
We also discuss the measurements of differential cross section
distributions of top quark pairs in the lepton plus jets channel.
Katerina Lipka
(Deutsches Elektronen-Synchrotron (DE))
23/07/2015, 15:42
Top and Electroweak Physics
talk
The results of phenomenological studies of top-quark pair production in proton-proton collisions are presented. Differential cross sections are calculated in perturbative QCD at approximate next-to-next-to-leading order ($\alpha_s^4$) by using methods of threshold resummation beyond the leading logarithmic accuracy. Predictions for the single-particle inclusive kinematics are presented for...
Eleni Ntomari
(Deutsches Elektronen-Synchrotron (DE))
23/07/2015, 16:30
Top and Electroweak Physics
talk
Precision measurements are presented of the top-quark pair inclusive production cross section in proton-proton collisions at the LHC at centre-of-mass energies of 7 !TeV and 8 !TeV. The data are collected with the CMS experiment during the years 2011 and 2012. The analyses include all top quark pair final states with the exception of events with two tau-leptons in the final state. In most...
Ulrich Husemann
(KIT - Karlsruhe Institute of Technology (DE))
23/07/2015, 16:48
Top and Electroweak Physics
talk
Differential top quark pair production cross sections are measured in proton-proton collisions at the LHC at centre-of-mass energies of 7 and 8 !TeV, using data collected by the CMS experiment in the years 2011 and 2012. The differential cross sections are measured as functions of various kinematic observables, including the transverse momentum and rapidity of the (anti)top quark and the...
Dr
Marino Romano
(INFN Bologna (IT))
23/07/2015, 17:06
Top and Electroweak Physics
talk
Measurements of the inclusive and differential topquark
pair and singletop
production
cross sections in protonproton
collisions with the ATLAS detector at the Large Hadron
Collider are presented. The inclusive measurements reach high precision and are
compared to the best available theoretical calculations. Differential measurements of the
kinematic properties of the top quark...
Olga Bessidskaia Bylund
(Stockholm University (SE))
23/07/2015, 17:24
Top and Electroweak Physics
talk
The large integrated luminosity provided by the LHC enables the production significant
numbers of top quark
pairs in association with addition jets or additional gauge bosons.
The production crosssection
of topquark
pairs in association with jets originating from
additional bquarks
is presented. This process is an important background to searches for
new physics and is compared to the...
Zoltan Laszlo Trocsanyi
(University of Debrecen (HU))
23/07/2015, 17:42
Top and Electroweak Physics
talk
We simulate the hadroproduction of a t tbar pair in association with one or two isolated photons at the LHC using the PowHel program. The generated events are stored according to the Les-Houches event format and constitute an almost inclusive event sample (regarding the photons), so that usual experimental photon isolation can be employed. We interface those events to the PYTHIA shower Monte...
gauhar abbas
(IFIC, Valencia)
24/07/2015, 09:00
Top and Electroweak Physics
talk
We perform a complete one-loop computation of {the two-body flavour-violating top decays $t \rightarrow c h$ and $t \rightarrow c V$ ($V= \gamma, Z$),} within the aligned two-Higgs-doublet model. We evaluate the impact of the model parameters on the associated branching {ratios,} taking into account constraints from flavour data and measurements of the {Higgs} properties. Assuming that...
Dr
Masaya Kohda
(Chung-Yuan Christian University)
24/07/2015, 09:18
Top and Electroweak Physics
talk
With a large amount of top and anti-top quarks produced at the LHC, rare top quark decays offer a nice probe to search for physics beyond the standard model. In this talk, I will discuss about a flavor-changing neutral current (FCNC) decay of the top quark by emitting a new massive gauge boson Z', namely, t --> c Z', based on a model of gauged L_mu - L_tau (the difference between the muon and...
Joseph Boudreau
(University of Pittsburgh (US))
24/07/2015, 09:36
Top and Electroweak Physics
talk
The top quark is the heaviest known fundamental particle and probing its couplings with
the other fundamental particle may open a window to physics beyond the Standard Model.
Searches for flavour changing neutral current top quark decays using the full 2012 ATLAS
dataset are presented. In addition, single top events are used to probe for anomalous
couplings between the top quark and the...
Zoltan Laszlo Trocsanyi
(University of Debrecen (HU))
24/07/2015, 09:54
Top and Electroweak Physics
talk
We present the computation of the differential cross section for the process pp -> W+ W- b bbar -> e mu b bbar + X at NLO~QCD accuracy matched to Shower Monte Carlo. We include all resonant and non-resonant contributions. This is achieved by fully taking into account the effect of off-shell t-quarks and off-shell W-bosons in the complex mass scheme. We also present a program called DECAYER...
Bijan Chokoufe
(DESY)
24/07/2015, 10:12
Top and Electroweak Physics
talk
Building on the new automatic subtraction of NLO amplitudes in WHIZARD,
we discuss our implementation of the POWHEG scheme to match the
radiative corrections consistently with the parton shower.
Doing so, we consider also the ambiguities involved in the selection of the
terms that are resummed to all orders. Although these ambiguities are of higher
order, they can be numerically...
Mr
Thomas Rauh
(TU Munich)
24/07/2015, 10:30
Top and Electroweak Physics
talk
A threshold scan of top-pair production at a future linear collider
allows to determine several standard model parameters with very high
precision. The recent completion of the third-order QCD corrections
to the inclusive top-pair production cross section demonstrates that
strong dynamics are under control. We investigate effects from
P-wave production and Higgs contributions at third...
Henning Kirschenmann
(CERN)
24/07/2015, 11:30
Top and Electroweak Physics
talk
Measurements of the top quark mass are presented using data collected by the CMS experiment in proton-proton collisions at the LHC at centre-of-mass energies of 7 and 8 TeV. Analyses in several decay channels of top quark pair events are employed to determine the top quark mass. The results are combined and compared to the world average.
Oleg Brandt
(Ruprecht-Karls-Universitaet Heidelberg (DE))
24/07/2015, 11:48
Top and Electroweak Physics
talk
The top quark mass is one of the fundamental parameters of the Standard Model. The
latest ATLAS measurements of the top quark mass are presented. A measurement using
lepton+jets events is presented, where a multidimensional
template fit is used to constrain
the uncertainties on the energy measurements of jets. The measurement is combined with
a measurement using dilepton events. In...
Boris Tuchming
(CEA Saclay)
24/07/2015, 12:06
Top and Electroweak Physics
talk
We report most recent measurements of the mass of the heaviest known
standard model particle, the top quark, performed by the D0 experiment at the
Fermilab Tevatron Collider. We present measurements in the lepton+jet and
dilepton decay channels. For these measurements the full D0 data set
corresponding to an integrated luminosity of 9.7 fb$^{-1}$ is used. We also
discuss a measurement of...
Jan Kieseler
(Deutsches Elektronen-Synchrotron (DE))
24/07/2015, 12:25
Top and Electroweak Physics
talk
Measurements of the top quark mass employing alternative methods are presented using data collected by the CMS experiment in proton-proton collisions at the LHC in the years 2011 and 2012 at centre-of-mass energies of 7 and 8 TeV. The alternative methods include the use of endpoint distributions as well as the study of possible model dependencies of the top mass measurement on the event...
Antoni Szczurek
(Institute of Nuclear Physics)
24/07/2015, 14:30
Top and Electroweak Physics
talk
$W^+ W^-$ production is one of the golden channels for testing the
Standard Model as well as for searches beyond the Standard Model.
We discuss many new subleading processes for inclusive production of
$W^+ W^-$ pairs not included in the literature so far.
We focus on photon-photon induced processes.
We include elastic-elastic, elastic-inelastic, inelastic-elastic
and...
Senka Duric
(University of Wisconsin (US))
24/07/2015, 14:48
Top and Electroweak Physics
talk
The recent multiboson measurements from CMS are interpreted in terms of constraints on anomalous triple and quartic gauge couplings.
Laurent Chevalier
(CEA/IRFU,Centre d'etude de Saclay Gif-sur-Yvette (FR))
24/07/2015, 15:06
Top and Electroweak Physics
talk
Measurements diboson production cross sections in proton-proton interactions at 7 and 8 TeV are reported from the ATLAS experiment. The cross section results are measured in phase space regions defined by the decay kinematics and then extrapolated to the full phase spaces. Cross sections for WV (V=W or Z) production in the leptonic or semileptonic channels are compared to (N)NLO predictions...
Phillip Russell Dudero
(Texas Tech University (US))
24/07/2015, 15:24
Top and Electroweak Physics
talk
We present studies of different multiboson final states in pp collisions at 8 TeV center-of-mass energy based on data recorded by the CMS detector at the LHC. These include precise measurements of W and Z production in association with a photon, diphoton,WW,WZ and ZZ as well as triboson production productions.
Lailin Xu
(Brookhaven National Laboratory (US))
24/07/2015, 15:42
Top and Electroweak Physics
talk
The ATLAS Collaboration has carried out the analysis of the inclusive four-lepton lineshape measurement using data corresponding to 20.3 fbโ1 of integrated luminosity from proton-proton collisions at โs= 8 TeV at the LHC collected with the ATLAS detector. The study focuses on the differential cross section as a function of the 4-lepton mass spectrum ranging from 80 to 1000 GeV where several...
Roger Barlow
(University of Huddersfield (GB))
25/07/2015, 09:00
Top and Electroweak Physics
talk
LHCb has a unique capability to separate beauty and charm jets. We present recent results on jet tagging performance, W+b,c jets and the observation of the top quark in the forward acceptance at the LHC.
Tom Neep
(University of Manchester (GB))
25/07/2015, 09:18
Top and Electroweak Physics
talk
The top quark is unique among the known quarks in that it decays before it has an
opportunity to form hadronic bound states. This makes measurements of its properties
particularly interesting as one can access directly the properties of a bare quark.
Measurements of the charge asymmetry in topquark
pair events are presented. The
measurements use both the 7 and 8 TeV ATLAS datasets and...
Frank Sebastian Roscher
(KIT - Karlsruhe Institute of Technology (DE))
25/07/2015, 09:36
Top and Electroweak Physics
talk
Measurements are presented of the properties of top quarks in pair production from proton-proton collisions at the LHC. The data were collected at pp centre-of-mass energies of 7 and 8 !TeV by the CMS experiment during the years 2011 and 2012. The charge asymmetry is measured using the difference of the absolute rapidities of the reconstructed top and anti-top kinematics, as well as from...
Ulrich Husemann
(KIT - Karlsruhe Institute of Technology (DE))
25/07/2015, 09:54
Top and Electroweak Physics
talk
We present recent measurements based on $t\bar t$ production in both the lepton+jets and dilepton channels using the D0 detector at the Fermilab Tevatron Collider. In both channels we measure angular distributions to extract the ttbar production forward-backward asymmetry and the top polarization in different basis. The full Run II D0 data sample corresponding to 9.7 fb$^{-1}$ of integrated...
Jonatan Piedra Gomez
(Universidad de Cantabria (ES))
25/07/2015, 10:13
Top and Electroweak Physics
talk
Several measurements of top quark properties in top quark decays are presented using data collected by the CMS experiment during the years 2011 and 2012. The polarization of W bosons in top quark decays is measured. The W-boson helicity fractions and angular asymmetries are extracted and limits on anomalous contributions to the Wtb vertex are determined. Furthermore, searches for...
Andres Tiko
(Nat. Inst. of Chem.Phys. & Biophys. (EE))
25/07/2015, 10:31
Top and Electroweak Physics
talk
Single top topologies are exploited for studies of top quark properties. This includes the first measurement of single top polarization in the t-channel production mode in pp collisions, which directly confirms the V-A nature of the tWb production vertex. W-helicity fractions are measured in the phase space sampled by a selection optimized for t-channel single top production, orthogonal to the...
Mogens Dam
(University of Copenhagen (DK))
25/07/2015, 11:30
Top and Electroweak Physics
talk
The prospects for electroweak precision measurements at the Future Circular Collider with electron-positron beams (FCC-ee) should provide improvements by a factor of order 25 over the present status, and constitute a broad search for the existence of new, weakly interacting particles up to very high energy scales. The Z mass and width, as well as the value of the electroweak mixing angle and b...
Zhiqing Philippe Zhang
(LAL, Orsay (FR))
25/07/2015, 11:50
Top and Electroweak Physics
talk
The LHeC is a proposed upgrade of the LHC to study ep/eA collisions in the TeV regime, by adding a 60 GeV electron beam through an Energy Recovery Linac. In ep, high precision electroweak and top physics can be performed, such as measurements of anomalous top couplings, for which simulation studies are presented, besides the prospect to access the top PDF.
Roman Poeschl
(Laboratoire de l'Accelerateur Lineaire (FR))
25/07/2015, 12:10
Top and Electroweak Physics
talk
The International Linear Collider and Compact Linear Collider projects aim to build a linear electron-positron collider with a center-of-mass energy well above the top quark pair production threshold. In this contribution an overview is presented of the potential of their top quark precision physics programme. One of the highlights is a precise determination of the top quark mass through a...
Patrick Janot
(CERN)
25/07/2015, 12:30
Top and Electroweak Physics
talk
With a centre-of-mass energy just above the top pair threshold production (โs ~ 365-370 GeV) and a luminosity of 1.8 10^34/cm2/s in up to four IPs, the FCC-ee can provide a measurement of the top quark to the photon and the Z with a precision below the per-cent level. This precision is reached with the sole angular and momentum distributions of the lepton arising from semi-leptonic decays in...
