J/psi and psi' production and their normal nuclear absorption in proton nucleus collisions at 400-GeV.

The NA50 collaboration Alessandro, B. ; Alexa, C. ; Arnaldi, R. ; et al.
Eur.Phys.J.C 48 (2006) 329, 2006.
Inspire Record 733916 DOI 10.17182/hepdata.57412

We report a new measurement of J/psi, psi' and Drell-Yan cross-sections, in the kinematical domain $-0.425<y_{\rm cm}<0.575$ and $-0.5<\cos\theta_{\rm CS}<0.5$, performed at the CERN-SPS using 400 GeV/c incident protons on Be, Al, Cu, Ag, W and Pb targets. The dependence of the charmonia production cross-sections on the size of the target nucleus allows to quantify the so-called normal nuclear absorption. In the framework of the Glauber model, this new measurement is combined with results previously obtained with the same apparatus, under different experimental conditions, and leads to a precise determination of the J/psi and psi' absorption cross-sections in the surrounding nuclear matter.

4 data tables

Production cross sections, per taregt nucleon for J/PSI and PSI(3685) and for Drell-Yann dimuon in the mass range of 2.9-4.5 GeV/c**, integrated in the phase space windows of the measurement.

Ratios of J/PSI, PSI(3685) and Drel Yann production cross sections, and for Drell-Yann dimuon in the mass range of 2.9-4.5 GeV/c**, integrated in the phase space windows of the measurement.

Absorption cross-section obtained with Glauber fits results only from this analysis.

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Bottomonium and Drell-Yan production in p-A collisions at 450 GeV

The NA50 collaboration Alessandro, B. ; Alexa, C. ; Arnaldi, R. ; et al.
Phys.Lett.B 635 (2006) 260-269, 2006.
Inspire Record 712992 DOI 10.17182/hepdata.57411

The NA50 Collaboration has measured heavy-quarkonium production in p-A collisions at 450 GeV incident energy (sqrt(s) = 29.1 GeV). We report here results on the production of the Upsilon states and of high-mass Drell-Yan muon pairs (m > 6 GeV). The cross-section at midrapidity and the A-dependence of the measured yields are determined and compared with the results of other fixed-target experiments and with the available theoretical estimates. Finally, we also address some issues concerning the transverse momentum distributions of the measured dimuons.

3 data tables

Drell-Yann (for the mass region MMUMU>6GeV/c**2) and bottomonium cross sections, and their ratio.

Mean pT and Mean PT**2 for Drell-Yann (4.5<MMUMU<8 GeV/c**2) Errors for Drell-Yann are purely statistical, error value for Upsilon includes a systematical error due to uncertianty in the extrapolation of the drell-yann yield into the upsilon region. The total error is anyway dominated by the statistical contribution.

ALPHA parameter.


Charmonia and Drell-Yan production in proton-nucleus collisions at the CERN SPS

The NA50 collaboration Alessandro, B ; Alexa, C ; Arnaldi, R ; et al.
Phys.Lett.B 553 (2003) 167-178, 2003.
Inspire Record 612573 DOI 10.17182/hepdata.29487

Charmonium production in p – A collisions is a unique tool for the study of the interaction of bound c c states in nuclear matter. It can provide details on the basic features of the resonance formation mechanism and, in particular, on its non-perturbative aspects. In this Letter, we present an experimental study of charmonia and Drell–Yan production in proton–nucleus collisions at 450 GeV/ c . The results are analyzed in the framework of the Glauber model and lead to the values of the nuclear absorption cross-section σ abs pA for J / ψ and ψ ′. Then, we compare the J / ψ absorption in proton–nucleus and sulphur–uranium interactions, using NA38 data. We obtain that, for the J / ψ , σ abs pA and σ abs SU are compatible, showing that no sizeable additional suppression mechanism is present in S–U collisions, and confirming that the anomalous J / ψ suppression only sets in for Pb–Pb interactions.

5 data tables

The J/PSI production cross section times the branching ratio to MU+ MU- pernucleon-nucleon collision for the differential nuclear targets.

The PSI(3685) production cross section times the branching ratio to MU+ MU-per nucleon-nucleon collision for the differential nuclear targets.

The Drell Yan cross section, divided by the mass number A, and multiplied by the isospin correction factors in the mass interval 2.9 to 4.5 GeV.

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Observation of polarization in bottomonium production at s**(1/2) = 38.8-GeV

The NuSea collaboration Brown, C.N. ; Awes, T.C. ; Beddo, M.E. ; et al.
Phys.Rev.Lett. 86 (2001) 2529-2532, 2001.
Inspire Record 536629 DOI 10.17182/hepdata.19423

We present a measurement of the polarization observed for bottomonium states produced in p-Cu collisions at sqrt(s)=38.8 GeV. The angular distribution of the decay dimuons of the Upsilon(1S) state show no polarization at small xF and pT but significant positive transverse production polarization for either pT > 1.8 GeV/c or for xF > 0.35. The Upsilon(2S+3S) unresolved states show a large transverse production polarization at all values of xF and pT measured. These observations are compared with an NRQCD calculation that predicts a transverse polarization in bottomonium production arising from quark-antiquark fusion and gluon-gluon fusion diagrams.

6 data tables

The observed polarization in the Drell-Yan sideband region as a function of PT. There is an additional systematic uncertainty of 0.02 in the polarization measurements.

The observed polarization in the Drell-Yan sideband region as a function of XL. There is an additional systematic uncertainty of 0.02 in the polarization measurements.

The observed polarization in the UPSILON(1S) region as a function of PT. There is an additional systematic error of 0.06 in the polarization measurements.

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Parton energy loss limits and shadowing in Drell-Yan dimuon production.

The NuSea collaboration Vasilev, M.A. ; Beddo, M.E. ; Brown, C.N. ; et al.
Phys.Rev.Lett. 83 (1999) 2304-2307, 1999.
Inspire Record 501230 DOI 10.17182/hepdata.19445

A precise measurement of the ratios of the Drell-Yan cross section per nucleon for an 800 GeV/c proton beam incident on Be, Fe and W targets is reported. The behavior of the Drell-Yan ratios at small target parton momentum fraction is well described by an existing fit to the shadowing observed in deep-inelastic scattering. The cross section ratios as a function of the incident parton momentum fraction set tight limits on the energy loss of quarks passing through a cold nucleus.

13 data tables

Ratios of measured cross sections per nucleon for Drell Yan events versus di-muon mass.

Ratios of measured cross sections per nucleon for Drell Yan events versus X2.

Ratios of measured cross sections per nucleon for Drell Yan events versus XL.

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Excess of continuum dimuon production at masses between threshold and the J/psi in S W interactions at 200-GeV/c/nucleon.

The HELIOS/3 collaboration Angelis, A.L.S. ; Antos, J. ; Beaulieu, M. ; et al.
Eur.Phys.J.C 13 (2000) 433-452, 2000.
Inspire Record 472127 DOI 10.17182/hepdata.49491

Results are presented on dimuon production for invariant masses ranging from the dimuon threshold up to the $J/\Psi$ meson. Proton-tungsten and sulphur-tungsten int

8 data tables

No description provided.

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Dimuon production below mass 3.1-GeV/c**2 in p W and S W interactions at 200-A/GeV/c

The HELIOS collaboration Masera, M. ;
Nucl.Phys.A 590 (1995) 93C-102C, 1995.
Inspire Record 407648 DOI 10.17182/hepdata.36493

The focus of this experiment is on dimuons at low M T but the mass range up to the J ψ is also covered. Dimuons are measured over a wide rapidity interval, ranging from nearly central to very forward rapidities. Experimental results concerning the vector meson production in p-W and S-W interactions at 200 GeV/c/A as a function of the charged multiplicity are presented together with a comparison of the observed invariant mass spectra with the dimuon conventional sources in the mass region between the φ and J ψ mesons. The observed large difference in the shape and absolute value of p-W and S-W dimuon spectra cannot be explained in terms of a direct extrapolation of the p-p results.

2 data tables

No description provided.

No description provided.


Dimuon and vector meson production in p W and S W interactions at 200-GeV/c/nucleon

The HELIOS/3 collaboration Mazzoni, M.A. ;
Nucl.Phys.A 566 (1994) 95C-102C, 1994.
Inspire Record 378632 DOI 10.17182/hepdata.36535

The focus of this experiment is on dimuons at low M T but the mass range up to the J ψ is also covered. Dimuons are measured over a wide rapidity interval, ranging from nearly central to very forward rapidities. We present the experimental results in different kinematic regions and as a function of charged multiplicity. The observed dimuon spectra are also compared to conventional sources of lepton pairs production.

5 data tables

No description provided.

No description provided.

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J / psi, psi-prime and muon pair production in p - W and S - U collisions

The NA38 collaboration Abreu, M.C. ; Baglin, C. ; Baldit, A. ; et al.
Nucl.Phys.A 566 (1994) 77C-85C, 1994.
Inspire Record 358346 DOI 10.17182/hepdata.36538

In this paper we present a study on the production of the J ψ and ψ′ resonances, decaying into muon pairs, in S-U collisions, at 200 GeV per incident nucleon. We find that the ratio between ψ′ and tJ ψ yields decreases as E T , the neutral transverse energy produced in the collision, increases. There is also a clear decrease of this ratio when going from p-W to S-U interactions. Assuming the high mass continuum to be Drell-Yan we discuss the possible understanding of the intermediate dimuon mass region as a superposition of Drell-Yan (extrapolated down in mass) and muon pairs from the semileptonic decays of charmed mesons. The p-W data is found to be explained by this procedure. However, the S-U data seems to be incompatible with a linear extrapolation from the proton-nucleus results.

4 data tables

THE NEUTRAL TRANSVERSE ENERGY PRODUCED IN THE COLLISION > 15 GEV.

THE NEUTRAL TRANSVERSE ENERGY PRODUCED IN THE COLLISION > 15 GEV.

THE NEUTRAL TRANSVERSE ENERGY PRODUCED IN THE COLLISION > 15 GEV.

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Limit on the anti-d / anti-u asymmetry of the nucleon sea from Drell-Yan production

McGaughey, P.L. ; Moss, J.M. ; Alde, D.M. ; et al.
Phys.Rev.Lett. 69 (1992) 1726-1728, 1992.
Inspire Record 344919 DOI 10.17182/hepdata.19848

We present an analysis of 800-GeV proton-induced Drell-Yan production data from isoscalar targets 2H and C, and from W, which has a large neutron excess. The ratio of cross sections per nucleon, R-σW/σIS, is sensitive to the difference between the d¯(x) and u¯(x) structure functions of the proton. We find that R is close to unity in the range 0.04≤x≤0.27, allowing upper limits to be set on the d¯-u¯ asymmetry. Additionally, the shape of the differential cross section m3 d2σ/dxF dm for 2H at xF≊0 shows no evidence of an asymmetric sea in the proton. We examine the implications of these data for various models of the violation of the Gottfried sum rule in deep-inelastic lepton scattering.

1 data table

Upper limit at the 2sigma statistical error level. Mass of MU+ MU- in GeV.