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Measurements of the kinematic distributions of J/ψ mesons produced in p−C, p−Ti and p−W collisions at √ s = 41.6 GeV in the Feynman-x region −0.34 < xF < 0.14 and for transverse momentum up to pT = 5.4 GeV/c are presented. The xF and pT dependencies of the nuclear suppression parameter, α, are also given. The results are based on 2.4 · 10 5 J/ψ mesons in(More)
The inclusive production cross sections of the strange vector mesons K * 0 , K * 0 , and φ have been measured in interactions of 920 GeV protons with C, Ti, and W targets with the HERA-B detector at the HERA storage ring. Differential cross sections as a function of rapidity and transverse momentum have been measured in the central rapidity region and for(More)
Angular distributions of leptons from J/ψ's produced in 920 GeV fixed-target proton-nucleus collisions Abstract. A study of the angular distributions of leptons from decays of J/ψ's produced in p-C and p-W collisions at √ s = 41.6 GeV has been performed in the J/ψ Feynman-x region −0.34 < xF < 0.14 and for J/ψ transverse momenta up to 5.4 GeV/c. The data(More)
A measurement of the polarization of Λ and Λ baryons produced in pC and pW collisions at √ s = 41.6 GeV has been performed with the HERA B spectrometer. The measurements cover the kinematic range of 0.6 GeV/c < p ⊥ < 1.2 GeV/c in transverse momentum and −0.15 < x F < 0.01 in Feynman-x. The polarization results from the two different targets agree within the(More)
The proton-nucleon cross section ratio R = Br(Υ → l + l −) · dσ(Υ)/dy| y=0 / σ(J/ψ) has been measured with the HERA-B spectrometer in fixed-target proton-nucleus collisions at 920 GeV proton beam energy corresponding to a proton-nucleon cms energy of √ s = 41.6 GeV. The combined results for the decay channels Υ → e + e − and Υ → µ + µ − yield a ratio R =(More)
The mid-rapidity (dσ pN /dy at y=0) and total (σ pN) production cross sections of J/ψ mesons are measured in proton-nucleus interactions. Data collected by the HERA-B experiment in interactions of 920 GeV/c protons with carbon, titanium and tungsten targets are used for this analysis. The J/ψ mesons are reconstructed by their decay into lepton pairs. The(More)
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