Search results for "Parto"

showing 10 items of 608 documents

Measurement of Z 0 -boson production at large rapidities in Pb–Pb collisions at

2018

The production of Z0 bosons at large rapidities in Pb–Pb collisions at √sNN=5.02TeV is reported. Z0 candidates are reconstructed in the dimuon decay channel (Z0→μ+μ−), based on muons selected with pseudo-rapidity −4.0 20GeV/c. The invariant yield and the nuclear modification factor, RAA, are presented as a function of rapidity and collision centrality. The value of RAA for the 0–20% central Pb–Pb collisions is 0.67±0.11(stat.)±0.03(syst.)±0.06(corr. syst.), exhibiting a deviation of 2.6σ from unity. The results are well-described by calculations that include nuclear modifications of the parton distribution functions, while the predictions using vacuum PDFs deviate from data by 2.3σ in the 0…

Nuclear reactionPhysicsNuclear and High Energy PhysicsLarge Hadron ColliderMuon010308 nuclear & particles physicsParton01 natural scienceslaw.inventionNuclear physicslaw0103 physical sciencesRapidityImpact parameter010306 general physicsColliderBoson
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Pathlength dependence of energy loss within in-medium showers

2010

Studying the pathlength dependence of high P_T hadron suppression in heavy-ion collisions by measuring the dependence of hard hadron production on the angle phi with the reaction plane in non-central collisions has so far been one of the most successful tools in constraining the microscopical picture of leading parton energy loss. With the imminent start of the LHC heavy-ion program and the possibility of full jet reconstruction, the focus has shifted to models which are capable of simulating full in-medium parton showers rather than tracing the leading parton only. Yet, on the level of single inclusive hadron observables, such shower models need to reproduce the findings of leading parton …

Nuclear reactionPhysicsNuclear and High Energy PhysicsParticle physicsLarge Hadron Colliderta114010308 nuclear & particles physicsPhysics::Instrumentation and DetectorsMonte Carlo methodHadronHigh Energy Physics::PhenomenologyFOS: Physical sciencesPartonObservableElementary particle01 natural sciencesNuclear physicsHigh Energy Physics - PhenomenologyHigh Energy Physics - Phenomenology (hep-ph)0103 physical sciencesProduction (computer science)High Energy Physics::Experiment010306 general physicsNuclear ExperimentPhysical Review C
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Constraints on nuclear parton distributions from dijet photoproduction at the LHC

2019

Using QCD calculations of the cross section of inclusive dijet photoproduction in Pb-Pb ultraperipheral collisions in the LHC kinematics as pseudo-data, we study the effect of including these data using the Bayesian reweighting technique on nCTEQ15, nCTEQ15np, and EPPS16 nuclear parton distribution functions (nPDFs). We find that, depending on the assumed error of the pseudo-data, it leads to a significant reduction of the nPDF uncertainties at small values of the momentum fraction $x_A$. Taking the error to be 5\%, the uncertainty of nCTEQ15 and nCTEQ15np nPDFs reduces approximately by a factor of two at $x_A=10^{-3}$. At the same time, the reweighting effect on EPPS16 nPDFs is much smalle…

PB-PB COLLISIONSParticle physicsNuclear TheoryPhysics and Astronomy (miscellaneous)FOS: Physical scienceslcsh:AstrophysicsPartonhiukkasfysiikka114 Physical sciences01 natural sciencesCOLLIDERNuclear Theory (nucl-th)MomentumCross section (physics)High Energy Physics - Phenomenology (hep-ph)lcsh:QB460-4660103 physical scienceslcsh:Nuclear and particle physics. Atomic energy. RadioactivityQuantum ChromodynamicsNuclear Experiment (nucl-ex)010306 general physicsNuclear ExperimentEngineering (miscellaneous)PhysicsQuantum chromodynamicsLarge Hadron Collider010308 nuclear & particles physicsHigh Energy Physics - Phenomenologynuclear parton distribution functionsDistribution functionlcsh:QC770-798ydinfysiikkaVECTOR-MESONSParametrization
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"Table 135" of "Measurements of $t\bar{t}$ differential cross-sections of highly boosted top quarks decaying to all-hadronic final states in $pp$ col…

2019

$m^{t\bar{t}}$ covariance matrix for absolute differential cross-section in parton level

PP -->$t\bar{t}$ ---> L_JET L_JET$m^{t\bar{t}}$High Energy Physics::PhenomenologyHigh Energy Physics::Experimentparton levelPP -->$t\bar{t}$ ---> all-hadronicNuclear Experiment13000
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"Table 87" of "Measurements of $t\bar{t}$ differential cross-sections of highly boosted top quarks decaying to all-hadronic final states in $pp$ coll…

2018

$m^{t\bar{t}}$ absolute differential cross-section in parton level

PP -->$t\bar{t}$ ---> L_JET L_JET$m^{t\bar{t}}$parton level13000
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"Table 102" of "Measurements of $t\bar{t}$ differential cross-sections of highly boosted top quarks decaying to all-hadronic final states in $pp$ col…

2019

$m^{t\bar{t}}$ normalized differential cross-section at parton level. The parton level phase-space is limited to the region $p_T^{t,1} > 500~$GeV, $p_T^{t,2} > 350~$GeV.

PP -->$t\bar{t}$ ---> L_JET L_JET$m^{t\bar{t}}$parton levelPP -->$t\bar{t}$ ---> all-hadronic13000
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"Table 147" of "Measurements of $t\bar{t}$ differential cross-sections of highly boosted top quarks decaying to all-hadronic final states in $pp$ col…

2018

${\chi}^{t\bar{t}}$ covariance matrix for absolute differential cross-section in parton level

PP -->$t\bar{t}$ ---> L_JET L_JET${\chi}^{t\bar{t}}$High Energy Physics::PhenomenologyHigh Energy Physics::Experimentparton levelNuclear Experiment13000
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"Table 149" of "Measurements of $t\bar{t}$ differential cross-sections of highly boosted top quarks decaying to all-hadronic final states in $pp$ col…

2018

${\chi}^{t\bar{t}}$ covariance matrix for relative differential cross-section in parton level

PP -->$t\bar{t}$ ---> L_JET L_JET${\chi}^{t\bar{t}}$High Energy Physics::PhenomenologyHigh Energy Physics::Experimentparton levelNuclear Experiment13000
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"Table 90" of "Measurements of $t\bar{t}$ differential cross-sections of highly boosted top quarks decaying to all-hadronic final states in $pp$ coll…

2018

${\chi}^{t\bar{t}}$ absolute differential cross-section in parton level

PP -->$t\bar{t}$ ---> L_JET L_JET${\chi}^{t\bar{t}}$parton level13000
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"Table 105" of "Measurements of $t\bar{t}$ differential cross-sections of highly boosted top quarks decaying to all-hadronic final states in $pp$ col…

2019

${\chi}^{t\bar{t}}$ relative differential cross-section in parton level

PP -->$t\bar{t}$ ---> L_JET L_JET${\chi}^{t\bar{t}}$parton levelPP -->$t\bar{t}$ ---> all-hadronic13000
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