0000000000376416

AUTHOR

Y. Ito

showing 2 related works from this author

Measurement of the relative yields of ψ(2S) to ψ(1S) mesons produced at forward and backward rapidity in p+p , p+Al , p+Au , and He3+Au collisions at…

2017

The PHENIX Collaboration has measured the ratio of the yields of ψ(2S) to ψ(1S) mesons produced in p+p, p+Al, p+Au, and He3+Au collisions at sNN=200 GeV over the forward and backward rapidity intervals 1.2<|y|<2.2. We find that the ratio in p+p collisions is consistent with measurements at other collision energies. In collisions with nuclei, we find that in the forward (p-going or He3-going) direction, the relative yield of ψ(2S) mesons to ψ(1S) mesons is consistent with the value measured in p+p collisions. However, in the backward (nucleus-going) direction, the ψ(2S) meson is preferentially suppressed by a factor of ∼2. This suppression is attributed in some models to the breakup of the w…

PhysicsParticle physicsMeson010308 nuclear & particles physicsBranching fractionHigh Energy Physics::LatticeHigh Energy Physics::PhenomenologyNuclear TheoryQuarkonium01 natural sciencesDeconfinementNuclear physicsExcited state0103 physical sciencesQuark–gluon plasmaHigh Energy Physics::ExperimentRapidityNuclear Experiment010306 general physicsGlauberPhysical Review C
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Measurements of e+e− pairs from open heavy flavor in p+p and d+A collisions at sNN=200 GeV

2017

We report a measurement of e+e− pairs from semileptonic heavy-flavor decays in p+p collisions at sNN=200 GeV. The e+e− pair yield from bb¯ and cc¯ is separated by exploiting a double differential fit done simultaneously in dielectron invariant mass and pT. We used three different event generators, pythia, mc@nlo, and powheg, to simulate the e+e− spectra from cc¯ and bb¯ production. The data can be well described by all three generators within the detector acceptance. However, when using the generators to extrapolate to 4π, significant differences are observed for the total cross section. These difference are less pronounced for bb¯ than for cc¯. The same model dependence was observed in alr…

Quantum chromodynamicsPhysicsParticle physics010308 nuclear & particles physicsDrell–Yan processParton01 natural sciencesSpectral lineNuclear physics0103 physical sciencesQuark–gluon plasmaRapidityInvariant massPerturbation theory (quantum mechanics)010306 general physicsPhysical Review C
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