0000000000078040

AUTHOR

A. Leisos

showing 42 related works from this author

Search for composite and exotic fermions at LEP 2

1999

A search for unstable heavy fermions with the DELPHI detector at LEP is reported. Sequential and non-canonical leptons, as well as excited leptons and quarks, are considered. The data analysed correspond to an integrated luminosity of about 48~pb$^{-1}$ at an $e^+e^-$ centre-of-mass energy of 183~GeV and about 20~pb$^{-1}$ equally shared between the centre-of-mass energies of 172~GeV and 161~GeV. The search for pair-produced new leptons establishes 95\% confidence level mass limits in the region between 70~GeV/$c^2$ and 90~GeV/$c^2$, depending on the channel. The search for singly produced excited leptons and quarks establishes upper limits on the ratio of the coupling of the excited fermio…

QuarkParticle physicsPhysics and Astronomy (miscellaneous)PAIR PRODUCTIONCHARGED HEAVY-LEPTONSFOS: Physical sciences7. Clean energy01 natural sciencesPartícules (Física nuclear)CROSS-SECTIONSHigh Energy Physics - ExperimentE(+)E(-) COLLISIONSBHABHA SCATTERINGHigh Energy Physics - Experiment (hep-ex)0103 physical sciencesMONTE-CARLO PROGRAM[PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex]RADIATIVE-CORRECTIONS010306 general physicsNuclear ExperimentEngineering (miscellaneous)PhysicsLuminosity (scattering theory)010308 nuclear & particles physicsHigh Energy Physics::PhenomenologyFermionCoupling (probability)Z0 DECAYSExcited stateHigh Energy Physics::ExperimentFísica nuclearROOT-S=161 GEVEXCITED LEPTONSCHARGED HEAVY-LEPTONS; MONTE-CARLO PROGRAM; EXCITED LEPTONS; E(+)E(-) COLLISIONS; Z0 DECAYS; ROOT-S=161 GEV; RADIATIVE-CORRECTIONS; BHABHA SCATTERING; PAIR PRODUCTION; CROSS-SECTIONSParticle Physics - ExperimentLepton
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Search for the Xb and other hidden-beauty states in the π+π−ϒ(1S) channel at ATLAS

2015

This Letter presents a search for a hidden-beauty counterpart of the X(3872) in the mass ranges 10.05--10.31 GeV and 10.40--11.00 GeV, in the channel Xb→π+π−Υ(1S)(→μ+μ−), using 16.2 fb−1 of s√=8 TeV pp collision data collected by the ATLAS detector at the LHC. No evidence for new narrow states is found, and upper limits are set on the product of the Xb cross section and branching fraction, relative to those of the Υ(2S), at the 95% confidence level using the CLS approach. These limits range from 0.8% to 4.0%, depending on mass. For masses above 10.1 GeV, the expected upper limits from this analysis are the most restrictive to date. Searches for production of the Υ(13DJ), Υ(10860), and Υ(110…

Nuclear physicsPhysicsNuclear and High Energy PhysicsPionLarge Hadron Collidermedicine.anatomical_structureChannel (digital image)MesonBranching fractionAtlas (anatomy)medicineQuarkoniumX(3872)Physics Letters B
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Measurement of exclusive γγ→ℓ+ℓ− production in proton–proton collisions at s=7 TeV with the ATLAS detector

2015

This Letter reports a measurement of the exclusive gamma gamma -> l(+)l(-) (l = e, mu) cross-section in proton-proton collisions at a centre-of-mass energy of 7 TeV by the ATLAS experiment at the LHC, based on an integrated luminosity of 4.6 fb(-1). For the electron or muon pairs satisfying exclusive selection criteria, a fit to the dilepton acoplanarity distribution is used to extract the fiducial cross-sections. The cross-section in the electron channel is determined to be sigma(excl)(gamma gamma -> e+e-) = 0.428 +/- 0.035 (stat.) +/- 0.018 (syst.) pbfor a phase-space region with invariant mass of the electron pairs greater than 24GeV, in which both electrons have transverse momentum p(T)…

PhysicsNuclear and High Energy PhysicsParticle physicsLarge Hadron ColliderMuonProtonATLAS experimentAcoplanarityNuclear physicsmedicine.anatomical_structureAtlas (anatomy)PseudorapiditymedicineHigh Energy Physics::ExperimentInvariant massNuclear ExperimentPhysics Letters B
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Probing the Quantum Interference between Singly and Doubly Resonant Top-Quark Production in pp Collisions at s=13  TeV with the ATLAS Detector

2018

This Letter presents a normalized differential cross-section measurement in a fiducial phase-space region where interference effects between top-quark pair production and associated production of a single top quark with a W boson and a b-quark are significant. Events with exactly two leptons (ee, μμ, or eμ) and two b-tagged jets that satisfy a multiparticle invariant mass requirement are selected from 36.1  fb^{-1} of proton-proton collision data taken at sqrt[s]=13  TeV with the ATLAS detector at the LHC in 2015 and 2016. The results are compared with predictions from simulations using various strategies for the interference. The standard prescriptions for interference modeling are signifi…

PhysicsParticle physicsTop quarkLarge Hadron Collider010308 nuclear & particles physicsHigh Energy Physics::PhenomenologyGeneral Physics and AstronomyCollision01 natural sciencesPair productionPhase space0103 physical sciencesInvariant mass010306 general physicsLeptonBosonPhysical Review Letters
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Measurements of four-lepton production in pp collisions at s=8 TeV with the ATLAS detector

2016

A search is presented for a high-mass Higgs boson in the , , , and decay modes using the ATLAS detector at the CERN Large Hadron Collider. The search uses proton-proton collision data at a centre-o ...

PhysicsNuclear and High Energy PhysicsParticle physicsLarge Hadron ColliderPhysics::Instrumentation and Detectors010308 nuclear & particles physicsAtlas (topology)Atlas detectorHigh Energy Physics::Phenomenology01 natural sciencesNuclear physics0103 physical sciencesHiggs bosonPhysics::Accelerator PhysicsHigh Energy Physics::ExperimentNuclear Experiment010306 general physicsLeptonPhysics Letters B
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Deep sea tests of a prototype of the KM3NeT digital optical module

2014

SIRE(opens in a new window)|View at Publisher| Export | Download | Add to List | More... European Physical Journal C Volume 74, Issue 9, 1 September 2014, 8p Deep sea tests of a prototype of the KM3NeT digital optical module: KM3NeT Collaboration (Article) Adrián-Martínez, S.a, Ageron, M.b, Aharonian, F.c, Aiello, S.d, Albert, A.e, Ameli, F.f, Anassontzis, E.G.g, Anghinolfi, M.h, Anton, G.i, Anvar, S.j, Ardid, M.a, de Asmundis, R.k, Balasi, K.l, Band, H.m, Barbarino, G.kn, Barbarito, E.o, Barbato, F.kn, Baret, B.p, Baron, S.p, Belias, A.lq, Berbee, E.m, van den Berg, A.M.r, Berkien, A.m, Bertin, V.b, Beurthey, S.b, van Beveren, V.m, Beverini, N.st, Biagi, S.uv, Bianucci, S.t, Billault, M.b,…

KM3NeT; digital optical modulePhysics - Instrumentation and Detectors[PHYS.ASTR.IM]Physics [physics]/Astrophysics [astro-ph]/Instrumentation and Methods for Astrophysic [astro-ph.IM]Physics and Astronomy (miscellaneous)TELESCOPEPhysics::Instrumentation and Detectorsdigital optical moduleFOS: Physical sciencesNeutrino Telescopesneutrino astrophysics; Cherenkov detector; Neutrino TelescopesKM3NeT; Cherenkov; UnderwaterDESIGNCherenkov[PHYS.PHYS.PHYS-INS-DET]Physics [physics]/Physics [physics]/Instrumentation and Detectors [physics.ins-det]Instrumentation and Methods for Astrophysics (astro-ph.IM)KM3NeTEngineering (miscellaneous)Astrophysics::Instrumentation and Methods for Astrophysicsneutrino telescopeDATA-ACQUISITIONInstrumentation and Detectors (physics.ins-det)READOUTneutrino astrophysics[SDU.ASTR.IM]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Instrumentation and Methods for Astrophysic [astro-ph.IM]NEUTRINOSUnderwaterAstrophysics - Instrumentation and Methods for AstrophysicsSYSTEMCherenkov detector
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Measurement of trilinear gauge couplings in e(+)e(-) collisions at 161 GeV and 172 GeV

1998

Trilinear gauge boson couplings are measured using data taken by DELPHI at 161 GeV and 172 GeV, Values for WWV couplings (V = Z,gamma) are determined from a study of the reactions e(+)e(-) --> W+W- and e(+)e(-) --> We nu, using differential distributions from the WW final state in which one W decays hadronically and the other leptonically, and total cross,section data from other channels, Limits are also derived on neutral ZV gamma couplings from an analysis of the reaction e(+)e(-) --> gamma + invisible particles. (C) 1998 Elsevier Science B.V.

Particle physicsNuclear and High Energy PhysicsElectron–positron annihilation7. Clean energy01 natural sciencesNuclear physics0103 physical sciencesOPTIMAL OBSERVABLES[PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex]010306 general physicsNuclear ExperimentOPTIMAL OBSERVABLES; PHOTON COUPLINGS; ROOT-S=1.8 TEVDELPHIPhysicsGauge boson010308 nuclear & particles physicsHigh Energy Physics::PhenomenologyROOT-S=1.8 TEVGauge (firearms)LARGE ELECTRON POSITRON COLLIDERPHOTON COUPLINGSLarge Electron–Positron ColliderPARTICLE PHYSICS; LARGE ELECTRON POSITRON COLLIDER; DELPHIPARTICLE PHYSICSHigh Energy Physics::ExperimentParticle Physics - Experiment
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Search for neutralino pair production at root s = 189 GeV

2001

A search for pair-production of neutralinos at a LEP centre-of-mass energy of 189 GeV gave no evidence for a signal. This limits the neutralino production cross-section and excludes regions in the parameter space of the Minimal Supersymmetric Standard Model (MSSM).

GRAVITINOSParticle physicsCOLLISIONSPhysics and Astronomy (miscellaneous)LOWEST ORDER CALCULATIONSMONTE-CARLO SIMULATIONFOS: Physical sciences2-PHOTON PROCESSESParameter space01 natural sciencesSignalPartícules (Física nuclear)High Energy Physics - ExperimentPHYSICSHigh Energy Physics - Experiment (hep-ex)0103 physical sciencesEVENT GENERATOR[PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex]RADIATIVE-CORRECTIONS010306 general physicsEngineering (miscellaneous)SUPERSYMMETRYDELPHIHIGH-ENERGIESPhysics010308 nuclear & particles physicsHigh Energy Physics::PhenomenologyLARGE ELECTRON POSITRON COLLIDERPair productionPARTICLE PHYSICS; LARGE ELECTRON POSITRON COLLIDER; DELPHINeutralinoPARTICLE PHYSICSFísica nuclearMONTE-CARLO SIMULATION; LOWEST ORDER CALCULATIONS; RADIATIVE-CORRECTIONS; 2-PHOTON PROCESSES; EVENT GENERATOR; HIGH-ENERGIES; SUPERSYMMETRY; PHYSICS; GRAVITINOS; COLLISIONSHigh Energy Physics::ExperimentEnergy (signal processing)Particle Physics - ExperimentMinimal Supersymmetric Standard ModelEUROPEAN PHYSICAL JOURNAL C
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Measurement of jet charge in dijet events froms=8  TeVppcollisions with the ATLAS detector

2016

The momentum-weighted sum of the charges of tracks associated to a jet is sensitive to the charge of the initiating quark or gluon. This paper presents a measurement of the distribution of momentum ...

QuarkQuantum chromodynamicsCoupling constantPhysicsParticle physics010308 nuclear & particles physicsScatteringAtlas detectorHigh Energy Physics::Latticemedia_common.quotation_subjectNuclear TheoryHigh Energy Physics::PhenomenologyPerturbative QCD01 natural sciencesAsymmetryGluonNuclear physics0103 physical sciencesHigh Energy Physics::Experiment010306 general physicsmedia_commonPhysical Review D
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A measurement of the Tau topological branching ratios

2001

Using data collected in the DELPHI detector at LEP-1, measurements of the inclusive tau branching ratios for decay modes containing one, three, or five charged particles have been performed, giving the following results: B_1 = B(\tau^- -> (particle)^- \geq 0pi^0 \geq 0K^0 \nu_\tau(\bar{\nu})) = (85.316 +/- 0.093 +/- 0.049)%; B_3 = B(\tau^- -> 2h^-h^+ \geq 0pi^0 \geq 0K^0 \nu_\tau) = (14.569 +/- 0.093 +/- 0.048)%; B_5 = B(\tau^- -> 3h^-2h^+ \geq 0pi^0 \geq 0K^0 \nu_\tau) = (0.115 +/- 0.013 +/- 0.006)%, where h is either a charged pi or K meson. The first quoted uncertainties are statistical and the second systematic.

Particle physicsPhysics and Astronomy (miscellaneous)MesonPAIR PRODUCTIONENERGIESFOS: Physical sciencesBranching (polymer chemistry)01 natural sciencesCROSS-SECTIONSHigh Energy Physics - ExperimentHigh Energy Physics - Experiment (hep-ex)BHABHA SCATTERINGMONTE-CARLOMONTE-CARLO; RADIATIVE-CORRECTIONS; BHABHA SCATTERING; PARTICLE PHYSICS; DELPHI DETECTOR; PAIR PRODUCTION; CROSS-SECTIONS; CP-INVARIANCE; ENERGIES; DECAY0103 physical sciences[PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex]RADIATIVE-CORRECTIONS010306 general physicsEngineering (miscellaneous)DELPHIPhysicshigh energy collider010308 nuclear & particles physicsLEPDELPHI DETECTORCharged particleFIS/01 - FISICA SPERIMENTALEPARTICLE PHYSICSHigh Energy Physics::ExperimentFísica nuclearCP-INVARIANCEDECAYParticle Physics - Experiment
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Measurement of the differential cross-section of highly boosted top quarks as a function of their transverse momentum ins=8  TeVproton-proton collisi…

2016

The differential cross-section for pair production of top quarks with high transverse momentum is measured in 20.3 fb(-1) of proton-proton collisions at a center-of-mass energy of 8 TeV. The measur ...

QuarkPhysicsTop quarkParticle physicsProton010308 nuclear & particles physicsHigh Energy Physics::PhenomenologyNuclear TheoryFunction (mathematics)01 natural sciences7. Clean energyNuclear physicsmedicine.anatomical_structurePair productionAtlas (anatomy)Phase space0103 physical sciencesTransverse momentummedicinePhysics::Accelerator PhysicsNuclear Experiment010306 general physicsPhysical Review D
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A search for $\eta'_c$ production in photon-photon fusion at LEP

1998

A search for the production of the $\eta'_c$ meson, the first radial excitation of the ground state of charmonium $\eta_c$(2980), in the photon-photon fusion reaction at LEP has been performed using the data collected by the DELPHI detector during 1992-1996. No evidence of $\eta'_c$ production is found in the mass region 3520--3800 MeV/c^2. An upper limit for the ratio of the two-photon widths of the $\eta'_c$ and $\eta_c$ is obtained.

Nuclear and High Energy PhysicsParticle physicsPhotonMesonHigh Energy Physics::LatticeWidth ratio01 natural sciencesPartícules (Física nuclear)High Energy Physics - ExperimentNuclear physics0103 physical sciences[PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex]Nuclear fusion010306 general physicsNuclear ExperimentDELPHIPhysicsFusion010308 nuclear & particles physicsHigh Energy Physics::PhenomenologyLARGE ELECTRON POSITRON COLLIDERLarge Electron–Positron ColliderPARTICLE PHYSICS; LARGE ELECTRON POSITRON COLLIDER; DELPHIPARTICLE PHYSICSFísica nuclearHigh Energy Physics::ExperimentGround stateExcitationParticle Physics - Experiment
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A Precise Measurement of the $\tau$ Polarisation at LEP-1

2000

The $\tau$ polarisation has been studied with the ${\rm e^+e^-}\to \tau^+\tau^-$ data collected by the DELPHI detector at LEP in 1993, 1994 and 1995 around the Z resonance firstly through the exclusive decay channels ${\rm e}\nu\bar{\nu}$ , $\mu\nu\bar{\nu}$ , $\pi\nu$ , $\rho\nu$ and ${\rm a}_1\nu$ and secondly with an inclusive hadronic analysis which benefits from a higher efficiency and a better systematic precision. The results have been combined with those previously published on 1990 to 1992 DELPHI data, to produce results which reflect the full LEP-1 statistics. The fit of the $\tau$ polarisation dependence on the production angle yielded the polarisation parameters ${\cal A}_{_{\sc…

Particle physicsCOLLISIONSscientific informationPOLARIZATIONPhysics and Astronomy (miscellaneous)LUND MONTE-CARLOENERGIESElectron–positron annihilationHadron01 natural sciencesComputer Science::Digital LibrariesDECAYSPartícules (Física nuclear)informationPHYSICSNEUTRINO HELICITYBHABHA SCATTERINGOpen Access0103 physical sciences[PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex]RADIATIVE-CORRECTIONSComputer Science::Symbolic Computation010306 general physicsEngineering (miscellaneous)LUND MONTE-CARLO; NEUTRINO HELICITY; MICHEL PARAMETERS; RADIATIVE-CORRECTIONS; BHABHA SCATTERING; DECAYS; POLARIZATION; PHYSICS; COLLISIONS; ENERGIESBhabha scatteringDELPHIPhysics010308 nuclear & particles physicscommunicationPhysicsHigh Energy Physics::PhenomenologyepistemologyWeinberg angleMICHEL PARAMETERSPolarization (waves)LARGE ELECTRON POSITRON COLLIDERPARTICLE PHYSICS; LARGE ELECTRON POSITRON COLLIDER; DELPHIMichel parametersPARTICLE PHYSICSAngular dependenceFísica nuclearHigh Energy Physics::ExperimentParticle Physics - ExperimentOpen Society InstituteLepton
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Identified charged particles in quark and gluon jets

2000

A sample of 2.2 million hadronic Z decays, selected from the data recorded by the Delphi detector at LEP during 1994-1995 was used for an improved measurement of inclusive distributions of pi+, K+ and p and their antiparticles in gluon and quark jets. The production spectra of the individual identified particles were found to be softer in gluon jets compared to quark jets, with a higher multiplicity in gluon jets as observed for inclusive charged particles. A significant proton enhancement in gluon jets is observed indicating that baryon production proceeds directly from colour objects. The maxima, xi^*, of the xi-distributions for kaons in gluon and quark jets are observed to be different.

QuarkAntiparticleParticle physicsPhysics and Astronomy (miscellaneous)High Energy Physics::LatticeHadronNuclear TheoryFOS: Physical sciences01 natural sciencesSpectral lineDECAYSPartícules (Física nuclear)High Energy Physics - ExperimentPHYSICSHigh Energy Physics - Experiment (hep-ex)0103 physical sciencesALGORITHMMultiplicity (chemistry)010306 general physicsNuclear ExperimentEngineering (miscellaneous)DELPHIPhysics010308 nuclear & particles physicsHigh Energy Physics::PhenomenologyMULTIPLICITYORDER QCD; MULTIPLICITY; ALGORITHM; PHYSICS; DECAYSLARGE ELECTRON POSITRON COLLIDERCharged particleGluonBaryonPARTICLE PHYSICS; LARGE ELECTRON POSITRON COLLIDER; DELPHIPARTICLE PHYSICSFísica nuclearHigh Energy Physics::ExperimentORDER QCDParticle Physics - Experiment
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Measurement of Higgs boson production in the diphoton decay channel inppcollisions at center-of-mass energies of 7 and 8 TeV with the ATLAS detector

2014

A measurement of the production processes of the recently discovered Higgs boson is performed in the two-photon final state using 4.5 fb(-1) of proton-proton collisions data at root s = 7 TeV and 20.3 fb(-1) at root s = 8 TeV collected by the ATLAS detector at the Large Hadron Collider. The number of observed Higgs boson decays to diphotons divided by the corresponding Standard Model prediction, called the signal strength, is found to be mu = 1.17 +/- 0.27 at the value of the Higgs boson mass measured by ATLAS, m(H) = 125.4 GeV. The analysis is optimized to measure the signal strengths for individual Higgs boson production processes at this value of m(H). They are found to be mu(ggF) = 1.32…

PhysicsNuclear and High Energy PhysicsParticle physicsPhotonLarge Hadron Collider010308 nuclear & particles physicsHigh Energy Physics::Phenomenology7. Clean energy01 natural sciencesStandard ModelVector bosonGluonNuclear physicsmedicine.anatomical_structure13. Climate actionAtlas (anatomy)0103 physical sciencesHiggs bosonmedicineHigh Energy Physics::ExperimentCenter of mass010306 general physicsPhysical Review D
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Update of the search for charginos nearly mass-degenerate with the lightest neutralino

2000

The data collected by DELPHI in 1998 at the centre-of-mass energy of 189 GeV have been used to update the search for charginos nearly mass-degenerate with the lightest supersymmetric particle, which is assumed to be the lightest neutralino. Mass differences below \Delta M = 3 GeV/c^2 are considered. No excess of events with respect to the Standard Model expectation has been observed, and exclusions in the plane of \Delta M versus chargino mass are given. The new \Delta M independent lower limit on the mass of the chargino is 62.4 GeV/c^2 in the higgsino scenario (which includes the gaugino mass unification scenario), if all sfermions are heavier than the lightest chargino. In the approximat…

Nuclear and High Energy PhysicsParticle physicsCOLLISIONSField (physics)LOWEST ORDER CALCULATIONSENERGIESMONTE-CARLO SIMULATIONFOS: Physical sciences2-PHOTON PROCESSES01 natural sciencesLightest Supersymmetric ParticlePartícules (Física nuclear)Standard ModelHigh Energy Physics - ExperimentHigh Energy Physics - Experiment (hep-ex)MONTE-CARLO SIMULATION; LOWEST ORDER CALCULATIONS; RADIATIVE-CORRECTIONS; 2-PHOTON PROCESSES; COLLISIONS; ENERGIES; PROGRAMChargino0103 physical sciencesPROGRAM[PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex]RADIATIVE-CORRECTIONSHiggsino010306 general physicsNuclear ExperimentDELPHIPhysics010308 nuclear & particles physicsHigh Energy Physics::PhenomenologyGauginoLEPLARGE ELECTRON POSITRON COLLIDERSfermionNeutralinoPARTICLE PHYSICS; LARGE ELECTRON POSITRON COLLIDER; DELPHIPARTICLE PHYSICSFísica nuclearHigh Energy Physics::ExperimentParticle Physics - Experiment
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Search for the sgoldstino at √s = 189 to 202 GeV.

2000

A search for the supersymmetric partner of the goldstino, the sgoldstino S, at LEP2 is presented. The production Sgamma followed by S decay into two gluons or into two photons was studied at 189 - 202 GeV LEP centre-of-mass energies. No evidence for the S production was found and limits on the S mass corresponding to different theory parameters are given.

PhysicsNuclear and High Energy PhysicsParticle physicsPhoton010308 nuclear & particles physicsHigh Energy Physics::Phenomenology01 natural sciencesPartícules (Física nuclear)GluonSgoldstino0103 physical sciencesHigh Energy Physics::ExperimentFísica nuclearGoldstino010306 general physics
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Measurements of spin correlation in top-antitop quark events from proton-proton collisions ats=7  TeVusing the ATLAS detector

2014

Measurements of spin correlation in top quark pair production are presented using data collected with the ATLAS detector at the LHC with proton-proton collisions at a center-of-mass energy of 7 TeV, corresponding to an integrated luminosity of 4.6 fb(-1). Events are selected in final states with two charged leptons and at least two jets and in final states with one charged lepton and at least four jets. Four different observables sensitive to different properties of the top quark pair production mechanism are used to extract the correlation between the top and antitop quark spins. Some of these observables are measured for the first time. The measurements are in good agreement with the Stan…

QuarkPhysicsNuclear and High Energy PhysicsParticle physicsTop quarkLarge Hadron Collider010308 nuclear & particles physicsHigh Energy Physics::PhenomenologyTevatron01 natural sciences7. Clean energyBottom quarkNuclear physicsPair production0103 physical sciencesHigh Energy Physics::Experiment010306 general physicsLeptonBosonPhysical Review D
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Search for neutral and charged Higgs bosons in $e^+ e^-$ collisions at $\sqrt{s}$= 161 GeV and 172 GeV

1998

A search for neutral and charged Higgs bosons has been performed in the data collected by the {\sc DELPHI} detector at centre-of-mass energies of 161~GeV and 172~GeV. The analysis assumes either the pair-production of charged Higgs bosons, ${\mathrm H}^{\pm}$, or the production of the lightest neutral Higgs boson, h, with either a Z or a neutral pseudoscalar Higgs boson, A. All final state topologies expected from the decay of h and A %neutral Higgs particles into hadrons or a pair of $\tau$ leptons, and from the decay of ${\mathrm H}^{\pm}$ %charged Higgs bosons into a pair of quarks or a $\tau \nu_{\tau}$ pair have been considered. %In the case of the associated production with a Z boson,…

QuarkParticle physicsPhysics and Astronomy (miscellaneous)LOWEST ORDER CALCULATIONSElectron–positron annihilationHigh Energy Physics::LatticeHadronMONTE-CARLO SIMULATIONSTANDARD MODEL2-PHOTON PROCESSES01 natural sciencesPartícules (Física nuclear)Nuclear physicsPHYSICS0103 physical sciences[PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex]RADIATIVE-CORRECTIONSNuclear Experiment010306 general physicsEngineering (miscellaneous)SUPERSYMMETRYDELPHIBosonPhysics010308 nuclear & particles physicsHigh Energy Physics::PhenomenologySupersymmetryE+E-ANNIHILATIONLARGE ELECTRON POSITRON COLLIDERMONTE-CARLO SIMULATION; LOWEST ORDER CALCULATIONS; E+E-ANNIHILATION; RADIATIVE-CORRECTIONS; 2-PHOTON PROCESSES; STANDARD MODEL; Z(0) DECAYS; PHYSICS; SUPERSYMMETRYZ(0) DECAYSPARTICLE PHYSICS; LARGE ELECTRON POSITRON COLLIDER; DELPHILarge Electron–Positron ColliderHiggs bosonPARTICLE PHYSICSFísica nuclearHigh Energy Physics::ExperimentParticle Physics - ExperimentLepton
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Performance of the upgraded PreProcessor of the ATLAS Level-1 Calorimeter Trigger

2020

The PreProcessor of the ATLAS Level-1 Calorimeter Trigger prepares the analogue trigger signals sent from the ATLAS calorimeters by digitising, synchronising, and calibrating them to reconstruct transverse energy deposits, which are then used in further processing to identify event features. During the first long shutdown of the LHC from 2013 to 2014, the central components of the PreProcessor, the Multichip Modules, were replaced by upgraded versions that feature modern ADC and FPGA technology to ensure optimal performance in the high pile-up environment of LHC Run 2. This paper describes the features of the newMultichip Modules along with the improvements to the signal processing achieved.

Physics - Instrumentation and Detectors:Kjerne- og elementærpartikkelfysikk: 431 [VDP]Computer sciencePhysics::Instrumentation and Detectors01 natural sciencesHigh Energy Physics - Experiment030218 nuclear medicine & medical imaginglaw.inventionSubatomär fysikHigh Energy Physics - Experiment (hep-ex)0302 clinical medicinelawSubatomic Physics[PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex]PreprocessorDetectors and Experimental Techniquesphysics.ins-detInstrumentationMathematical PhysicsFPGASettore FIS/01Signal processingLarge Hadron ColliderInstrumentation and Detectors (physics.ins-det)trigger [calorimeter]ATLASCalorimeters; Trigger concepts and systems (hardware and software)Calorimetermedicine.anatomical_structure:Nuclear and elementary particle physics: 431 [VDP]Trigger concepts and systems (hardware and software)design [electronics]Particle Physics - ExperimentComputer hardwareperformanceCiências Naturais::Ciências Físicas530 Physics:Ciências Físicas [Ciências Naturais]Analog-to-digital converterFOS: Physical sciences61003 medical and health sciencesCalorimetersAtlas (anatomy)0103 physical sciencesmedicineHigh Energy Physicsddc:610[PHYS.PHYS.PHYS-INS-DET]Physics [physics]/Physics [physics]/Instrumentation and Detectors [physics.ins-det]Field-programmable gate arraysignal processingCalorimeterScience & Technologyhep-ex010308 nuclear & particles physicsbusiness.industrycalorimeter: trigger530 Physikcalibrationanalog-to-digital converterpile-upExperimental High Energy Physicselectronics: readoutbusinessreadout [electronics]Energy (signal processing)electronics: design
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Measurement of trilinear gauge boson couplings WWV, (V Z,gamma) in e(+)e(-) collisions at 189 GeV

2001

Measurements of the trilinear gauge boson couplings WWgamma and WWZ are presented using the data taken by DELPHI in 1998 at a centre-of-mass energy of 189 GeV and combined with DELPHI data at 183 GeV. Values are determined for Delta(g_1^Z) and Delta(kappa_gamma), the differences of the WWZ charge coupling and of the WWgamma dipole coupling from their Standard Model values, and for lambda_gamma, the WWgamma quadrupole coupling. A measurement of the magnetic dipole and electric quadrupole moment of the W is extracted from the results for Delta(kappa_gamma) and lambda_gamma. The study uses data from the final states jjlv, jjjj, lX, jjX and gammaX, where j represents a quark jet, l an identifie…

QuarkNuclear and High Energy PhysicsParticle physicsENERGIESAstrophysics::High Energy Astrophysical Phenomenastandard modelLEP-IIFOS: Physical sciencesLambda7. Clean energy01 natural sciencesPartícules (Física nuclear)High Energy Physics - ExperimentStandard ModelEVENTSHigh Energy Physics - Experiment (hep-ex)BHABHA SCATTERINGMONTE-CARLO0103 physical sciencesOPTIMAL OBSERVABLES[PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex]W-MASSgauge couplings010306 general physicsDETECTORQCDELPHIPhysicsGauge boson010308 nuclear & particles physicsHigh Energy Physics::PhenomenologyCharge (physics)LARGE ELECTRON POSITRON COLLIDERFIS/01 - FISICA SPERIMENTALECol·lisions (Física nuclear)QuadrupolePARTICLE PHYSICS; LARGE ELECTRON POSITRON COLLIDER; DELPHIOPTIMAL OBSERVABLES; BHABHA SCATTERING; MONTE-CARLO; W-MASS; LEP-II; EVENTS; DETECTOR; DELPHI; E+E-->W+W; ENERGIESelectron-positron collisionPARTICLE PHYSICSFísica nuclearHigh Energy Physics::ExperimentE+E-->W+WMagnetic dipoleLepton
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Search for supersymmetric particles in scenarios with a gravitino LSP and stau NLSP

2000

Sleptons, neutralinos and charginos were searched for in the context of scenarios where the lightest supersymmetric particle is the gravitino. It was assumed that the stau is the next-to-lightest supersymmetric particle. Data collected with the DELPHI detector at a centre-of-mass energy near 189 GeV were analysed combining the methods developed in previous searches at lower energies. No evidence for the production of these supersymmetric particles was found. Hence, limits were derived at 95% confidence level.

NEUTRALINOSParticle physicsPhysics and Astronomy (miscellaneous)LOWEST ORDER CALCULATIONSPAIR PRODUCTIONENERGIESMONTE-CARLO SIMULATIONpluridisciplinarityFOS: Physical sciences2-PHOTON PROCESSESContext (language use)01 natural sciencesLightest Supersymmetric ParticlePartícules (Física nuclear)High Energy Physics - ExperimentHigh Energy Physics - Experiment (hep-ex)E(+)E(-) COLLISIONS0103 physical sciences[PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex]RADIATIVE-CORRECTIONSontology010306 general physicsEngineering (miscellaneous)DELPHIPhysics010308 nuclear & particles physicsHigh Energy Physics::PhenomenologyreflexivityLEPscience studiesepistemologieLARGE ELECTRON POSITRON COLLIDERhistory of sciencePARTICLE PHYSICS; LARGE ELECTRON POSITRON COLLIDER; DELPHIMONTE-CARLO SIMULATION; LOWEST ORDER CALCULATIONS; RADIATIVE-CORRECTIONS; PAIR PRODUCTION; E(+)E(-) COLLISIONS; 2-PHOTON PROCESSES; ENERGIES; BREAKING; LEP; NEUTRALINOSParticlePARTICLE PHYSICSGravitinoFísica nuclearHigh Energy Physics::ExperimentcomplexityParticle Physics - ExperimentBREAKING
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Study of dimuon production in photon-photon collisions and measurement of QED photon structure functions at LEP

2001

Muon pair production in the process e+e- -> e+e-mu+mu- is studied using the data taken at LEP1 (sqrt(s) \simeq m_Z) with the DELPHI detector during the years 1992-1995. The corresponding integrated luminosity is 138.5 pb^{-1}. The QED predictions have been tested over the whole Q^2 range accessible at LEP1 (from several GeV^2/c^4 to several hundred GeV^2/c^4) by comparing experimental distributions with distributions resulting from Monte Carlo simulations using various generators. Selected events are used to extract the leptonic photon structure function F_2^\gamma. Azimuthal correlations are used to obtain information on additional structure functions, F_A^\gamma and F_B^\gamma, which orig…

Particle physicsE+E ANNIHILATIONPhotonPhysics and Astronomy (miscellaneous)PAIR PRODUCTIONAstrophysics::High Energy Astrophysical Phenomena4-LEPTON FINAL-STATES; GAMMA-GAMMA-COLLISIONS; MONTE-CARLO SIMULATION; PAIR PRODUCTION; AZIMUTHAL CORRELATIONS; RADIATIVE-CORRECTIONS; E+E ANNIHILATION; MUON PAIRS; 4TH ORDER; SCATTERINGMONTE-CARLO SIMULATIONMonte Carlo methodFOS: Physical sciences01 natural sciences7. Clean energyPartícules (Física nuclear)High Energy Physics - ExperimentAZIMUTHAL CORRELATIONSHigh Energy Physics - Experiment (hep-ex)4TH ORDER0103 physical sciences[PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex]RADIATIVE-CORRECTIONSSCATTERING010306 general physicsEngineering (miscellaneous)DELPHIPhysicsMuonLuminosity (scattering theory)010308 nuclear & particles physicsMUON PAIRSHigh Energy Physics::PhenomenologyGAMMA-GAMMA-COLLISIONSLARGE ELECTRON POSITRON COLLIDERPhoton structure function3. Good healthScattering amplitude4-LEPTON FINAL-STATESPair productionPARTICLE PHYSICS; LARGE ELECTRON POSITRON COLLIDER; DELPHIPARTICLE PHYSICSProduction (computer science)Física nuclearHigh Energy Physics::ExperimentParticle Physics - Experiment
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Deep sea tests of a prototype of the KM3NeT digital optical module: KM3NeT Collaboration

2014

The first prototype of a photo-detection unit of the future KM3NeT neutrino telescope has been deployed in the deep waters of the Mediterranean Sea. This digital optical module has a novel design with a very large photocathode area segmented by the use of 31 three inch photomultiplier tubes. It has been integrated in the ANTARES detector for in-situ testing and validation. This paper reports on the first months of data taking and rate measurements. The analysis results highlight the capabilities of the new module design in terms of background suppression and signal recognition. The directionality of the optical module enables the recognition of multiple Cherenkov photons from the same $^{40…

PhysicsPhotomultiplierPhotonPhysics and Astronomy (miscellaneous)010308 nuclear & particles physicsbusiness.industryPhysics::Instrumentation and DetectorsDetectorAstrophysics::Instrumentation and Methods for Astrophysics01 natural sciencesSignalPhotocathodeOpticsKM3NeT0103 physical sciences14. Life underwaterSensitivity (control systems)010306 general physicsbusinessEngineering (miscellaneous); Physics and Astronomy (miscellaneous)Engineering (miscellaneous)Cherenkov radiation
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Single intermediate vector boson production in e(+)e(-) collisions at root s=183 and 189 GeV

2001

The cross sections for the production of single charged and neutral intermediate vector bosons were measured using integrated luminosities of 52 pb-1 and 154 pb-1 collected by the experiment at centre-of-mass energies of 182.6 GeV and 188.6 GeV, respectively. The cross sections for the reactions were determined in limited kinematic regions. The results found are in agreement with the Standard Model predictions for these channels. © 2001 Elsevier Science B.V.

Nuclear and High Energy PhysicsParticle physicsLOWEST ORDER CALCULATIONSMONTE-CARLO SIMULATIONFOS: Physical sciences2-PHOTON PROCESSESKinematics01 natural sciencesPartícules (Física nuclear)Standard ModelVector bosonHigh Energy Physics - ExperimentPHYSICSHigh Energy Physics - Experiment (hep-ex)BHABHA SCATTERINGLEP20103 physical sciencesPROGRAM[PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex]DELPHIPhysics010304 chemical physics010308 nuclear & particles physicsCOUPLINGSLARGE ELECTRON POSITRON COLLIDERPhysique atomique et nucléaire3. Good healthMONTE-CARLO SIMULATION; LOWEST ORDER CALCULATIONS; 2-PHOTON PROCESSES; BHABHA SCATTERING; PROGRAM; DELPHI; COUPLINGS; COLLIDERS; PHYSICS; LEP2COLLIDERSPARTICLE PHYSICS; LARGE ELECTRON POSITRON COLLIDER; DELPHIPARTICLE PHYSICSProduction (computer science)High Energy Physics::ExperimentParticle Physics - Experiment
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Observation and Measurement of Forward Proton Scattering in Association with Lepton Pairs Produced via the Photon Fusion Mechanism at ATLAS

2020

The observation of forward proton scattering in association with lepton pairs (eþe− þ p or μþμ− þ p) produced via photon fusion is presented. The scattered proton is detected by the ATLAS Forward Proton spectrometer, while the leptons are reconstructed by the central ATLAS detector. Proton-proton collision data recorded in 2017 at a center-of-mass energy of ffiffiffi s p ¼ 13 TeV are analyzed, corresponding to an integrated luminosity of 14.6 fb−1. A total of 57 (123) candidates in the ee þ p (μμ þ p) final state are selected, allowing the background-only hypothesis to be rejected with a significance exceeding 5 standard deviations in each channel. Proton-tagging techniques are introduced f…

:Kjerne- og elementærpartikkelfysikk: 431 [VDP]Photon13000 GeV-cmsLHC ATLASmeasured [channel cross section]General Physics and Astronomy01 natural sciences7. Clean energyHigh Energy Physics - Experimentelectron: pair productionSubatomär fysikHigh Energy Physics - Experiment (hep-ex)Integrated LuminosityFusion Mechanismphoton photon: fusionspectrometer [p]Subatomic Physics[PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex]scattering [p p]pair production [lepton]Electroweak interactionQuantum ChromodynamicsParticle productionNuclear ExperimentSettore FIS/01PhysicsQuantum chromodynamicsObservation and MeasurementQuantum electrodynamicsLarge Hadron Colliderp: spectrometerdimuonAtlas (topology)COLLISIONS; PHYSICS; GAMMA; LIGHT; LHCElectroweak interactionDetectorphotonATLASfusion [photon photon]muon: pair production:Nuclear and elementary particle physics: 431 [VDP]PhotoproductionLIGHTCERN LHC CollATLAS DetectorsLHCcolliding beams [p p]channel cross section: measuredParticle Physics - Experimentsmall-angleParticle physicsp p: scatteringCOLLISIONSp: particle identificationCiências Naturais::Ciências Físicas530 Physicslepton: pair production:Ciências Físicas [Ciências Naturais]Particles & FieldsFOS: Physical sciencesparticle identification [p]LHC ATLAS High Energy PhysicsPHYSICS0103 physical sciencesddc:530Cross-Section Measurementpair production [electron]pair production [muon]High Energy Physics010306 general physicsCiencias ExactasATLAS CollaborationScience & TechnologySpectrometerhep-exPomeronsFísicaGAMMALeptonsProton Scatteringexclusive productionPrecision measurementsProton Proton CollisionsStandard DeviationExperimental High Energy PhysicsElementary Particles and FieldsHigh Energy Physics::ExperimentHadron-hadron collisionsp p: colliding beamsLeptonacceptanceexperimental results
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Measurement of the transverse spin correlation in Z → τ+ τ- decays

1997

The measurement of the correlation between the transverse spin components of tau(+)tau(-) pairs collected during 1992 to 1994 with the DELPHI detector at LEP1 is presented. A value C-TT = 0.87 +/- 0.20 (stat.)(-0.12)(+0.10) (syst.) was obtained for the correlation parameter, in agreement with the Standard Model expectation. (C) 1997 Published by Elsevier Science B.V.

QuarkNuclear and High Energy PhysicsParticle physicsLUND MONTE-CARLOElectron–positron annihilationLEP-SLC ENERGIES01 natural sciencesPartícules (Física nuclear)JET FRAGMENTATIONStandard ModelNuclear physicsPHYSICS0103 physical sciencesRADIATIVE-CORRECTIONS010306 general physicsNuclear ExperimentDetectors de radiacióLUND MONTE-CARLO; LEP-SLC ENERGIES; RADIATIVE-CORRECTIONS; JET FRAGMENTATION; TAU-POLARIZATION; SIMULATION; PHYSICS; QUARKSpin-½DELPHIPhysics010308 nuclear & particles physicsTAU-POLARIZATIONQUARKCenter (category theory)LARGE ELECTRON POSITRON COLLIDERTransverse planePARTICLE PHYSICS; LARGE ELECTRON POSITRON COLLIDER; DELPHISIMULATIONPARTICLE PHYSICSHigh Energy Physics::ExperimentAstrophysics::Earth and Planetary Astrophysics
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Measurement of the spin density matrix for the rho(0), K*(0)(892) and phi produced in Z(0) decays

1997

The spin density matrix elements for the rho(0), K-*0(892) and phi produced in hadronic Z(0) decays are measured in the DELPHI detector. There is no evidence for spin alignment of the K-*0(892) and phi, in the region x(p) less than or equal to 0.3 (x(p) = p/p(beam)), where rho(00) = 0.33 +/- 0.05 and rho(00) = 0.30 +/- 0.04, respectively. In the fragmentation region, x(p) greater than or equal to 0.4, there is some indication for spin alignment of the rho(0) and K-*0(892), since rho(00) = 0.43 +/- 0.05 and rho(00) = 0.46 +/- 0.08, respectively. These values are compared with those found in meson-induced hadronic reactions. For the phi, rho(00) = 0.30 +/- 0.04 for x(p) greater than or equal …

Nuclear and High Energy PhysicsMesonElectron–positron annihilationD-STARHadronANNIHILATIONSPartícules (Física nuclear)QUARK FRAGMENTATION; D-STAR; ANNIHILATIONS; HADRONS; MESONSNuclear physicsAngular distribution[PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex]Matrix elementSpin densityDetectors de radiacióDELPHIPhysicsHADRONSD-STARQUARK FRAGMENTATIONLARGE ELECTRON POSITRON COLLIDERMESONSPARTICLE PHYSICS; LARGE ELECTRON POSITRON COLLIDER; DELPHIMass spectrumPARTICLE PHYSICSAtomic physicsParticle Physics - ExperimentPHYSICS LETTERS B
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A study of the Lorentz structure in tau decays

2000

This paper describes a measurement of the Michel parameters, \eta, \rho, \xi, \xi\delta, and the average \nu_{\tau} helicity, h_{\nu_{\tau}}, in tau lepton decays together with the first measurement of the tensor coupling in the weak charged current. The tau+tau- pairs were produced at the LEP e+e- collider at CERN from 1992 through 1995 in the DELPHI detector. Assuming lepton universality in the decays of the tau the measured values of the parameters were: \eta = -0.005 +/- 0.036 +/- 0.037, \rho = 0.775 +/- 0.023 +/- 0.020, \xi = 0.929 +/- 0.070 +/- 0.030, \xi\delta = 0.779 +/- 0.070 +/- 0.028, h_{\nu_{\tau}} = -0.997 +/- 0.027 +/- 0.011. The strength of the tensor coupling was measured to…

Particle physicsPhysics and Astronomy (miscellaneous)CHARGED WEAK-INTERACTIONSLUND MONTE-CARLOENERGIESLorentz transformationFOS: Physical sciences01 natural sciencesJET FRAGMENTATIONPartícules (Física nuclear)law.inventionHigh Energy Physics - Experimentsymbols.namesakeHigh Energy Physics - Experiment (hep-ex)NEUTRINO HELICITYLUND MONTE-CARLO; CHARGED WEAK-INTERACTIONS; RIGHT-SYMMETRICAL MODEL; MICHEL PARAMETERS; NEUTRINO HELICITY; RADIATIVE-CORRECTIONS; JET FRAGMENTATION; ENERGIES; LEPTON; PARTICLESlaw0103 physical sciences[PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex]RADIATIVE-CORRECTIONSPARTICLESTensor010306 general physicsColliderLEPTONEngineering (miscellaneous)Charged currentDELPHIPhysics010308 nuclear & particles physicsMICHEL PARAMETERSCoupling (probability)HelicityLARGE ELECTRON POSITRON COLLIDERRIGHT-SYMMETRICAL MODELPARTICLE PHYSICS; LARGE ELECTRON POSITRON COLLIDER; DELPHIsymbolsMichel parametersPARTICLE PHYSICSFísica nuclearHigh Energy Physics::ExperimentAstrophysics::Earth and Planetary AstrophysicsParticle Physics - ExperimentLeptonEuropean physical journal : C : particles and fields
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Search for a fermiophobic Higgs at LEP 2

2001

Higgs bosons predicted by the fermiophobic scenario within Two Higgs Doublets Models were searched for in the data collected by the DELPHI detector at centre-of-mass energies between 189 GeV and 202 GeV, corresponding to a total integrated luminosity of 380 pb^{-1}. No signal was found and confidence limits were derived in the framework of possible extensions of the Standard Model Higgs sector.

BOSONSNuclear and High Energy PhysicsParticle physicsENERGIESQUARK PAIR PRODUCTION; CARLO PROGRAM KORALZ; MONTE-CARLO; BHABHA SCATTERING; SUPERSYMMETRY; PHOTONS; PHYSICS; BOSONS; ANNIHILATION; ENERGIESFOS: Physical sciencesPHOTONS01 natural sciencesPartícules (Física nuclear)High Energy Physics - ExperimentHiggs sectorStandard ModelPHYSICSHigh Energy Physics - Experiment (hep-ex)BHABHA SCATTERINGCARLO PROGRAM KORALZMONTE-CARLO0103 physical sciences[PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex]010306 general physicsANNIHILATIONSUPERSYMMETRYBosonDELPHIPhysicsLuminosity (scattering theory)010308 nuclear & particles physicsDetectorHigh Energy Physics::PhenomenologyQUARK PAIR PRODUCTIONLARGE ELECTRON POSITRON COLLIDERPARTICLE PHYSICS; LARGE ELECTRON POSITRON COLLIDER; DELPHIHiggs bosonPARTICLE PHYSICSFísica nuclearHigh Energy Physics::ExperimentParticle Physics - Experiment
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Measurement of photon?jet transverse momentum correlations in 5.02 TeV Pb + Pb and pp collisions with ATLAS

2019

Jets created in association with a photon can be used as a calibrated probe to study energy loss in the medium created in nuclear collisions. Measurements of the transverse momentum balance between isolated photons and inclusive jets are presented using integrated luminosities of 0.49 nb−1 of Pb + Pb collision data at TeV and 25 pb−1 of pp collision data at TeV recorded with the ATLAS detector at the LHC. Photons with transverse momentum GeV and are paired with all jets in the event that have GeV and pseudorapidity . The transverse momentum balance given by the jet-to-photon ratio, , is measured for pairs with azimuthal opening angle . Distributions of the per-photon jet yield as a function…

PhotonLEAD-LEAD COLLISIONS; PP COLLISIONS; ROOT-S(NN)=2.76 TEV; DEPENDENCEheavy ion: scatteringPhysics::Instrumentation and DetectorsMonte Carlo methodRelativistic heavy ion collisionsphoton–jet transverse momentum correlationsnucl-ex01 natural sciencesHigh Energy Physics - ExperimentDouble Drell–YanSubatomär fysikHigh Energy Physics - Experiment (hep-ex)Double parton-scatteringDEPENDENCESubatomic Physicsscattering [p p][PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex]luminositiesCollisions ROOT-S(NN)=2.76 TEVNuclear Experiment (nucl-ex)Nuclear Experimentdimension: 2GeneralLiterature_REFERENCE(e.g.dictionariesencyclopediasglossaries)Nuclear ExperimentMonte CarloComputingMilieux_MISCELLANEOUSQCComputer Science::DatabasesPhysicsJet (fluid)Large Hadron ColliderSettore FIS/01 - Fisica Sperimentalephotonyield [jet]transverse momentum: correlationATLASlcsh:QC1-999:Mathematics and natural scienses: 400::Physics: 430::Nuclear and elementary particle physics: 431 [VDP]medicine.anatomical_structureCERN LHC Coll2 [dimension]nuclear matterLHCLEAD-LEAD COLLISIONSjet: yieldParticle Physics - ExperimentNuclear and High Energy Physicsp p: scatteringenergy loss [parton]530 PhysicsCiências Naturais::Ciências FísicasAstrophysics::High Energy Astrophysical Phenomena:Ciências Físicas [Ciências Naturais]FOS: Physical sciencesddc:500.2LHC ATLAS High Energy Physics[PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex]jets Nuclear physicsAtlas (anatomy)0103 physical sciencesCalibrationmedicineddc:530RapidityNuclear Physics - Experiment5020 GeV-cms/nucleonHigh Energy Physics010306 general physicsCiencias ExactasFour-lepton productionHiggs golden decay channelPP COLLISIONSScience & Technology010308 nuclear & particles physicshep-exHigh Energy Physics::Phenomenologynucleus:Matematikk og naturvitenskap: 400::Fysikk: 430::Kjerne- og elementærpartikkelfysikk: 431 [VDP]FísicaNuclear mattercalibrationjet quenching* Automatic Keywords *rapidityExperimental High Energy PhysicsHigh Energy Physics::Experimentparton: energy losscorrelation [transverse momentum]lcsh:Physicsexperimental resultsPhysics Letters B
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Search for dark matter in events with heavy quarks and missing transverse momentum in [Formula: see text] collisions with the ATLAS detector.

2014

This article reports on a search for dark matter pair production in association with bottom or top quarks in \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$20.3 \mathrm {~fb}^{-1}$$\end{document}20.3fb-1 of \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$pp$$\end{document}pp collisions collected at \documentclass[12pt]{minimal} \use…

Regular Article - Experimental PhysicsThe European physical journal. C, Particles and fields
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Measurement of D⁎±, D± and Ds± meson production cross sections in pp collisions at s=7 TeV with the ATLAS detector

2016

The production of D*(+/-), D-+/- and D-S(+/-) charmed mesons has been measured with the ATLAS detector in pp collisions at,/7s = 7 TeV at the LHC, using data corresponding to an integrated luminosi ...

Quantum chromodynamicsPhysicsNuclear and High Energy PhysicsParticle physicsMeson productionLarge Hadron ColliderMesonPhysics::Instrumentation and Detectors010308 nuclear & particles physicsAtlas detectorHigh Energy Physics::PhenomenologyDeep inelastic scattering01 natural sciences7. Clean energymedicine.anatomical_structureAtlas (anatomy)0103 physical sciencesTransverse momentummedicineHigh Energy Physics::ExperimentNuclear Experiment010306 general physicsNuclear Physics B
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Determination of |Vub|/|Vcb| with DELPHI at LEP

2001

The ratio of the CKM quark-mixing matrix elements |Vub|/|Vcb| has been measured using B hadron semileptonic decays. The analysis uses the reconstructed mass M_X of the secondary hadronic system produced in association with an identified lepton. Since B -> X_u lepton anti-nu transitions are characterised by hadronic masses below those of the D mesons produced in B -> X_c lepton anti-nu transitions, events with a reconstructed value of M_X significantly below the D mass are selected. Further signal enrichments are obtained using the topology of reconstructed decays and hadron identification. A fit to the numbers of decays in the b -> u enriched and depleted samples with M_X above and…

Nuclear and High Energy PhysicsParticle physicsMesonHadronFOS: Physical sciences01 natural sciencesPartícules (Física nuclear)High Energy Physics - ExperimentHigh Energy Physics - Experiment (hep-ex)0103 physical sciencesNuclear Experiment010306 general physicsDELPHIPhysicsEnergy distribution010308 nuclear & particles physicsBranching fractionHigh Energy Physics::PhenomenologyRest frameLARGE ELECTRON POSITRON COLLIDERPARTICLE PHYSICS; LARGE ELECTRON POSITRON COLLIDER; DELPHIPARTICLE PHYSICSFísica nuclearHigh Energy Physics::ExperimentParticle Physics - ExperimentLeptonPhysics Letters B
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A Search for Heavy Stable and Long-Lived Squarks and Sleptons in $e^+ e^-$ Collisions at Energies from 130 to 183 GeV

1998

A search for stable and long-lived heavy charged particles used the data taken by the DELPHI experiment at energies from 130 to 183 GeV. The Cherenkov light detected in the Ring Imaging Cherenkov Detector and the ionization loss measured in the Time Projection Chamber identify heavy particles from masses of 2 to nearly 89 GeV/c$^2$. Upper limits are given on the production cross-section and masses of sleptons, free squarks with a charge of $q = \pm 2/3e$ and hadronizing squarks. A search for stable and long-lived heavy charged particles used the data taken by the DELPHI experiment at energies from 130 to 183 GeV. The Cherenkov light detected in the Ring Imaging Cherenkov Detector and the io…

Nuclear and High Energy PhysicsParticle physicsPhysics::Instrumentation and DetectorsFOS: Physical sciences01 natural sciencesRing-imaging Cherenkov detectorPartícules (Física nuclear)High Energy Physics - ExperimentPHYSICSHigh Energy Physics - Experiment (hep-ex)Ionization0103 physical sciencesCHARGED-PARTICLES; SUPERSYMMETRY; PHYSICS; LEP[PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex]010306 general physicsNuclear ExperimentSUPERSYMMETRYCherenkov radiationDELPHIPhysicsTime projection chamber010308 nuclear & particles physicsHigh Energy Physics::PhenomenologyCharge (physics)LEPLARGE ELECTRON POSITRON COLLIDERCharged particleCHARGED-PARTICLESPARTICLE PHYSICS; LARGE ELECTRON POSITRON COLLIDER; DELPHIPARTICLE PHYSICSFísica nuclearHigh Energy Physics::ExperimentParticle Physics - Experiment
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Measurement of the mass of the W boson using direct reconstruction at √s = 183 GeV

1999

From data corresponding to an integrated luminosity of 53.5 pb(-1) taken during the 183 GeV run in 1997, DELPHI has measured the W mass from direct reconstruction of WW --> lq (q) over bar and WW --> q (q) over bar q (q) over bar events. Combining these channels, a value of m(w) = 80.238 +/- 0.154(stat) +/- 0.035(syst) +/- 0.035(fsi) +/- 0.021 (LEP) GeV/c(2) is obtained, where fsi denotes final state interaction. Combined with the W mass obtained by DELPHI from the WW production cross-section and with the direct measurement at 172 GeV this leads to a measured value of m(w) = 80.270 +/- 0.137(stat) +/- 0.031(syst) +/- 0.030(fsi) +/- 0.021(LEP)GeV/c(2), in good agreement with the Standard Mod…

Nuclear and High Energy PhysicsParticle physicsEINSTEIN CORRELATIONSCLUSTERING-ALGORITHMElectron–positron annihilationMathematicsofComputing_GENERALCOLOR DIPOLE MODEL01 natural sciencesComputer Science::Digital LibrariesPartícules (Física nuclear)LuminosityStandard ModelPHYSICSEVENTSNuclear physicsLEP20103 physical sciencesMONTE-CARLO PROGRAM[PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex]ANNIHILATION010306 general physicsDELPHIPhysicsAnnihilation010308 nuclear & particles physicsE(+)E(-) INTERACTIONSTheoryofComputation_GENERALLARGE ELECTRON POSITRON COLLIDERMONTE-CARLO PROGRAM; PAIR CROSS-SECTION; COLOR DIPOLE MODEL; E(+)E(-) INTERACTIONS; EINSTEIN CORRELATIONS; CLUSTERING-ALGORITHM; ANNIHILATION; PHYSICS; EVENTS; LEP2PARTICLE PHYSICS; LARGE ELECTRON POSITRON COLLIDER; DELPHIComputer Science::Mathematical SoftwarePARTICLE PHYSICSProduction (computer science)Física nuclearPAIR CROSS-SECTIONParticle Physics - ExperimentBar (unit)
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Consistent measurements of alpha(s) from precise oriented event shape distributions

2000

An updated analysis using about 1.5 million events recorded at $\sqrt{s} = M_Z$ with the DELPHI detector in 1994 is presented. Eighteen infrared and collinear safe event shape observables are measured as a function of the polar angle of the thrust axis. The data are compared to theoretical calculations in ${\cal O} (\alpha_s^2)$ including the event orientation. A combined fit of $\alpha_s$ and of the renormalization scale $x_{\mu}$ in $\cal O(\alpha_s^2$) yields an excellent description of the high statistics data. The weighted average from 18 observables including quark mass effects and correlations is $\alpha_s(M_Z^2) = 0.1174 \pm 0.0026$. The final result, derived from the jet cone energ…

QuarkParticle physicsPhysics and Astronomy (miscellaneous)OPTIMIZED PERTURBATION-THEORY; JET CROSS-SECTIONS; E+ E ANNIHILATION; QUANTUM CHROMODYNAMICS; E(+)E(-) ANNIHILATION; QCD CALCULATIONS; Z0 RESONANCE; MONTE-CARLO; DECAYS; ALPHA(S)(M(Z)(2))QCD CALCULATIONSFOS: Physical sciencesScale (descriptive set theory)01 natural sciences7. Clean energyDECAYSPartícules (Física nuclear)High Energy Physics - ExperimentRenormalizationHigh Energy Physics - Experiment (hep-ex)MONTE-CARLO0103 physical sciences[PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex]Engineering (miscellaneous); Physics and Astronomy (miscellaneous)010306 general physicsEngineering (miscellaneous)ALPHA(S)(M(Z)(2))DELPHIPhysicsQUANTUM CHROMODYNAMICS010308 nuclear & particles physicsHigh Energy Physics::PhenomenologyOrder (ring theory)ObservableFunction (mathematics)E(+)E(-) ANNIHILATIONLARGE ELECTRON POSITRON COLLIDEROrientation (vector space)Experimental uncertainty analysisOPTIMIZED PERTURBATION-THEORYPARTICLE PHYSICS; LARGE ELECTRON POSITRON COLLIDER; DELPHIPARTICLE PHYSICSJET CROSS-SECTIONSFísica nuclearHigh Energy Physics::ExperimentE+ E ANNIHILATIONZ0 RESONANCEParticle Physics - Experiment
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Cross-sections and leptonic forward-backward asymmetries from the Z(0) running of LEP

2000

During 1993 and 1995 LEP was run at 3 energies near the Z $^0$ peak in order to give improved measurements of the mass and width of the resonance. During 1994, LEP operated only at the Z $^0$ peak. In total DELPHI accumulated data corresponding to an integrated luminosity of approximately 116 pb $^{-1}$ . Analyses of the hadronic cross-sections and of the cross-sections and forward-backward asymmetries in the leptonic channels used the most precise evaluations of the LEP energies. In the dimuon channel, events with a photon radiated from the initial state have been used to probe the cross-sections and asymmetries down to PETRA energies. Model independent fits to all DELPHI lineshape and asy…

Particle physicsE+E ANNIHILATIONPhysics and Astronomy (miscellaneous)Electron–positron annihilationSQUARE-ROOT-S=29 GEVHadronCHARGE ASYMMETRIES01 natural sciencesResonance (particle physics)LuminosityStandard ModelNuclear physicsMONTE-CARLOSLC ENERGIES0103 physical sciences[PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex]RADIATIVE-CORRECTIONSANGLE BHABHA SCATTERING010306 general physicsEngineering (miscellaneous)DELPHIPhysics010308 nuclear & particles physicsHigh Energy Physics::PhenomenologyOrder (ring theory)Weinberg angleMUON-PAIR PRODUCTIONSQUARE-ROOT-SLARGE ELECTRON POSITRON COLLIDEROF-MASS ENERGIESPARTICLE PHYSICS; LARGE ELECTRON POSITRON COLLIDER; DELPHILarge Electron–Positron ColliderPARTICLE PHYSICSHigh Energy Physics::ExperimentFísica nuclearMUON-PAIR PRODUCTION; ANGLE BHABHA SCATTERING; OF-MASS ENERGIES; SQUARE-ROOT-S; MONTE-CARLO; RADIATIVE-CORRECTIONS; SQUARE-ROOT-S=29 GEV; CHARGE ASYMMETRIES; E+E ANNIHILATION; SLC ENERGIESParticle Physics - Experiment
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Performance of $b$-Jet Identification in the ATLAS Experiment

2016

We thank CERN for the very successful operation of the LHC, as well as the support staff from our institutions without whom ATLAS could not be operated efficiently. We acknowledge the support of ANPCyT, Argentina; YerPhI, Armenia; ARC, Australia; BMWFW and FWF, Austria; ANAS, Azerbaijan; SSTC, Belarus; CNPq and FAPESP, Brazil; NSERC, NRC and CFI, Canada; CERN; CONICYT, Chile; CAS, MOST and NSFC, China; COLCIENCIAS, Colombia; MSMT CR, MPO CR and VSC CR, Czech Republic; DNRF, DNSRC and Lundbeck Foundation, Denmark; IN2P3-CNRS, CEA-DSM/IRFU, France; GNSF, Georgia; BMBF, HGF, and MPG, Germany; GSRT, Greece; RGC, Hong Kong SAR, China; ISF, I-CORE and Benoziyo Center, Israel; INFN, Italy; MEXT an…

detector-systems performancePerformance of High Energy Physics Detectorsecondary [vertex]Elementary particle01 natural sciencesPARTONlaw.inventionSubatomär fysikCHANNELcluster findingscattering [p p]impact parameterGeneralLiterature_REFERENCE(e.g.dictionariesencyclopediasglossaries)протон-протонные столкновенияQBLarge detector-systems performanceHigh energy physics detectorLarge Hadron ColliderLarge detector systems for particle and astroparticle physics; Large detector-systems performance; Pattern recognition cluster finding calibration and fitting methods; Performance of High Energy Physics Detectors; Instrumentation; Mathematical Physicstrack data analysisQUARK PAIR PRODUCTIONbottom [jet]CERN LHC CollPattern recognition cluster finding calibration and fitting method7000 GeV-cmscolliding beams [p p]performanceHADRONIC COLLISIONSCiências Naturais::Ciências FísicasLarge detectorFitting methodHigh energy physicATLAS LHC High Energy Physics510 MathematicsmuonDISTRIBUTIONSUncertainty analysis Astroparticle physicHigh Energy Physics010306 general physicsSystematic uncertainties AlgorithmsAstroparticle physicsCalibration and fitting methodsScience & Technology010308 nuclear & particles physicsLarge detector systems for particle and astroparticle physicsParticle acceleratorRangingPerformance of High Energy PhysicsCOLLIDERScorrelationExperimental High Energy PhysicsPerformance of High Energy Physics DetectorshadronATLAS детекторБольшой адронный коллайдерcharm [jet]Elementary particleHigh Energy Physics - ExperimentHigh Energy Physics - Experiment (hep-ex)lawSubatomic Physics[PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex]Detectors and Experimental TechniquesInstrumentationUncertainty analysisMathematical PhysicsPhysicsPattern recognition cluster finding calibration and fitting methods4. EducationATLAS experimentSettore FIS/01 - Fisica SperimentaleDetectorsflavor [jet]calibration and fitting methodsATLASLarge Hadron ColliderLarge detector systems for particle and astroparticle physics; Large; detector-systems performance; Pattern recognition cluster finding; calibration and fitting methods; Performance of High Energy Physics; Detectors; PRODUCTION CROSS-SECTION; QUARK PAIR PRODUCTION; ROOT-S=7 TEV; PARTON; DISTRIBUTIONS; HADRONIC COLLISIONS; MATRIX-ELEMENTS; LHC; COLLIDERS; DETECTOR; CHANNEL8. Economic growthCalibrationparticle identification [bottom]LHCImpact parameterParticle Physics - ExperimentParticle physicsdata analysis method530 Physics:Ciências Físicas [Ciências Naturais]FOS: Physical sciences530MATRIX-ELEMENTSparticle identification [charm]on-line [trigger]Pattern recognition0103 physical sciencesComplementary methodddc:610DETECTORROOT-S=7 TEVCluster findingFísicaLarge detector systems for particle and astroparticle physics; Large detector-systems performance; Pattern recognition cluster finding calibration and fitting methods; Performance of High Energy Physics DetectorsPattern recognition systemcalibrationtracksPRODUCTION CROSS-SECTIONefficiencyHadronLarge detector systems for particle and astroparticle physicLargeHigh Energy Physics::ExperimentStatistical correlationstatisticalexperimental results
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Centrality, rapidity, and transverse momentum dependence of isolated prompt photon production in lead-lead collisions atsNN=2.76TeV measured with the…

2016

Prompt photon production in root S-NN = 2.76-TeV Pb + Pb collisions has been measured by the ATLAS experiment at the Large Hadron Collider using data collected in 2011 with an integrated luminosity ...

PhysicsParticle physicsPhotonLarge Hadron ColliderLuminosity (scattering theory)Physics::Instrumentation and Detectors010308 nuclear & particles physicsAtlas detectorAstrophysics::High Energy Astrophysical PhenomenaATLAS experiment01 natural sciences7. Clean energyNuclear physics0103 physical sciencesTransverse momentumHigh Energy Physics::ExperimentRapidityNuclear Experiment010306 general physicsPhysical Review C
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Transverse momentum, rapidity, and centrality dependence of inclusive charged-particle production in sNN=5.02 TeV p+ Pb collisions measured by the AT…

2016

Measurements of the per-event charged-particle yield as a function of the charged-particle transverse momentum and rapidity are performed using p+Pbp+Pb collision data collected by the ATLAS experiment at the LHC at a centre-of-mass energy of sqrt (SNN) = 5.01 TeV. Charged particles are reconstructed over pseudorapidity |η|<2.3|η|<2.3 and transverse momentum between 0.1 GeV0.1 GeV and 22 GeV22 GeV in a dataset corresponding to an integrated luminosity of 1 μb−11 μb−1. The results are presented in the form of charged-particle nuclear modification factors, where the p+Pbp+Pb charged-particle multiplicities are compared between central and peripheral p+Pbp+Pb collisions as well as to charged-p…

PhysicsNuclear and High Energy PhysicsParticle physicsLarge Hadron ColliderLuminosity (scattering theory)Proton010308 nuclear & particles physics01 natural sciencesCharged particleNuclear physicsPseudorapidity0103 physical sciencesRapidityNuclear Experiment010306 general physicsNucleonGlauberPhysics Letters B
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Measurements of the trilinear gauge boson couplings WWV (V = $\gamma$ Z) in e$^+$e$^-$ collisions at 183 GeV

1999

Measurements of the trilinear gauge boson couplings WWγ and WWZ are presented from data taken by DELPHI in 1997 at an energy of 183 GeV. From a study of the reactions e + e − → W + W − , e + e − → Weν and e + e − → ννγ , values are obtained for Δg 1 Z and Δκ γ , the differences of the WWZ charge coupling and of the WWγ dipole couplings from their Standard Model values, and for λ γ , the WWγ quadrupole coupling. The observations are consistent with the predictions of the Standard Model. (Elsevier)

Nuclear and High Energy PhysicsParticle physicsElectron–positron annihilation7. Clean energy01 natural sciencesPartícules (Física nuclear)Standard ModelNuclear physics0103 physical sciences[PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex]010306 general physicsEvent generatorDELPHICouplingPhysicsGauge boson010308 nuclear & particles physicsHigh Energy Physics::PhenomenologyCharge (physics)LARGE ELECTRON POSITRON COLLIDERDipolePARTICLE PHYSICS; LARGE ELECTRON POSITRON COLLIDER; DELPHIQuadrupolePARTICLE PHYSICSFísica nuclearHigh Energy Physics::Experiment
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