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rivet Analysis
Measurement of the underlying event in the Drell-Yan process in proton-proton collisions at sqrt(s) = 7 TeV

The CMS collaboration Chatrchyan, Serguei ; Khachatryan, Vardan ; Sirunyan, Albert M ; et al.

Eur.Phys.J.C 72 (2012) 2080, 2012.

Inspire Record 1107658 DOI 10.17182/hepdata.68072

A measurement of the underlying event (UE) activity in proton-proton collisions at a center-of-mass energy of 7 TeV is performed using Drell--Yan events in a data sample corresponding to an integrated luminosity of 2.2 inverse femtobarns, collected by the CMS experiment at the LHC. The activity measured in the muonic final state (q q-bar to opposite-sign muons) is corrected to the particle level and compared with the predictions of various Monte Carlo generators and hadronization models. The dependence of the UE activity on the dimuon invariant mass is well described by PYTHIA and HERWIG++ tunes derived from the leading jet/track approach, illustrating the universality of the UE activity. The UE activity is observed to be independent of the dimuon invariant mass in the region above 40 GeV, while a slow increase is observed with increasing transverse momentum of the dimuon system. The dependence of the UE activity on the transverse momentum of the dimuon system is accurately described by MADGRAPH, which simulates multiple hard emissions.

20 data tables

Table 1

Toward $N_\text{chg}$ density vs $p_\perp^{\mu\mu}$.

Table 2

Transverse $N_\text{chg}$ density vs $p_\perp^{\mu\mu}$.

Table 3

Away $N_\text{chg}$ density vs $p_\perp^{\mu\mu}$.

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Kinematic distributions and nuclear effects of $J/\psi$ production in 920 GeV fixed-target proton-nucleus collisions

The HERA-B collaboration Abt, I. ; Adams, M. ; Agari, M. ; et al.

Eur.Phys.J.C 60 (2009) 525-542, 2009.

Inspire Record 804247 DOI 10.17182/hepdata.57472

Measurements of the kinematic distributions of $J/\psi$ mesons produced in $p-$C, $p-$Ti and $p-$W collisions at $\sqrt{s}=41.6 \mathrm{GeV}$ in the Feynman-$x$ region $-0.34 < x_{F} < 0.14$ and for transverse momentum up to $p_T = 5.4 \mathrm{GeV}/c$ are presented. The $x_F$ and $p_T$ dependencies of the nuclear suppression parameter, $\alpha$, are also given. The results are based on $2.4 \cdot 10^{5}$ $J/\psi$ mesons in both the $e^+ e^-$ and $\mu^{+}\mu^{-}$ decay channels. The data have been collected by the HERA-B experiment at the HERA proton ring of the DESY laboratory. The measurement explores the negative region of $x_{F}$ for the first time. The average value of $\alpha$ in the measured $x_{F}$ region is $0.981 \pm 0.015$. The data suggest that the strong nuclear suppression of $J/\psi$ production previously observed at high $x_F$ turns into an enhancement at negative $x_F$.

4 data tables

Table 1

J/PSI distributions (dN/dp_T, normalized to their integrals over the measured range) for three targets materials with statistical and systematics uncertainties.

Table 2

J/PSI distributions (dN/dx_F, normalized to their integrals over the measured range) for three targets materials with statistical and systematics uncertainties.

Table 3

The parameter Alpha as a function of p_T. Statistical and systematic uncertainties are indicated separately.

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Transverse momentum distributions of J/psi, psi', Drell-Yan and continuum dimuons produced in Pb Pb interactions at the SPS.

The NA50 collaboration Abreu, M.C ; Alessandro, B ; Alexa, C ; et al.

Phys.Lett.B 499 (2001) 85-96, 2001.

Inspire Record 537484 DOI 10.17182/hepdata.57431

Muon pairs produced in Pb–Pb interactions at 158 GeV/ c per nucleon are used to study the transverse momentum distributions of the J/ ψ , ψ ′ and dimuons in the mass continuum. In particular, the dependence of these distributions on the centrality of the Pb–Pb collision is investigated in detail.

9 data tables

Table 1

Mean values of PT and PT**2 calculated from the IMR distributions.

Table 2

Mean values of PT and PT**2 calculated from the J/PSI distributions.

Table 3

Mean values of PT and PT**2 calculated from the PSI(3685) distributions.

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Transverse momentum of J/psi, psi' and mass continuum muon pairs produced in S-32 U collisions at 200-GeV/c per nucleon.

The NA38 collaboration Abreu, M.C ; Astruc, J ; Baglin, C ; et al.

Phys.Lett.B 423 (1998) 207-212, 1998.

Inspire Record 467276 DOI 10.17182/hepdata.40524

We have studied the production of J/ ψ , ψ ′ and prompt muon pairs in the mass continuum from a sample of sulfur-uranium interactions at 200 GeV/c per nucleon. We report, in this letter, results obtained for the transverse momentum distributions and their dependence on the transverse energy released in the collision, used as an estimator of the centrality of the nucleus-nucleus interaction.

11 data tables

Table 1

No description provided.

Table 2

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Table 3

No description provided.

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Production of $\rho^+$, $\rho^-$, $\rho^0$ (770), $\eta$ (550), $\omega(783)$ and F2 (1270) Mesons in Anti-nucleon Neon and Neutrino Neon Charged Current Interactions

The BEBC WA59 collaboration Wittek, W. ; Aderholz, M. ; Allport, P. ; et al.

Z.Phys.C 44 (1989) 175, 1989.

Inspire Record 278996 DOI 10.17182/hepdata.15079

The production of the meson resonances ϱ(770) (all three charge states), η(550), ω(783) andf2(1270) in$\bar v$ Ne and ν Ne charged current interactions is investigated in a bubble chamber experiment with BEBC at CERN. Except for thef2, the main features of resonance production are reasonably well described by the Lund model, although the average resonance multiplicities are overestimated by the model by (67±30)%. The average multiplicities of all resonances, including thef2, are well reproduced by a semiempirical model, whose parameters were determined from hadron interaction data.

21 data tables

Table 1

No description provided.

Table 2

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Table 3

No description provided.