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Dimuon production in collisions of proton, oxygen and sulfur ions on heavy targets at 200 GeV/nucleon; $J/\psi$ production, $\pi$ and $K$ distributions

The NA38 collaboration Grossiord, J.Y. ; Abreu, M.C. ; Alimi, M. ; et al.
Nucl.Phys.A 498 (1989) 249-260, 1989.
Inspire Record 1392869 DOI 10.17182/hepdata.36947

The dimuon production in 200 GeV/nucleon O-U, O-Cu, S-U and p-U reactions is studied in function of transverse energy E T produced by the collision. The J / ψ production relative to continuum events is suppressed for heavy ion induced reactions when E T increases. This suppression is enhanced at low transverse momentum. The π and K meson distributions extracted from the data, have, for each reaction, a similar average transverse momentum which increases only slightly with the transverse energy.

3 data tables

No description provided.

No description provided.

No description provided.


Charmonia production in 450-GeV/c proton induced reactions.

The NA38 collaboration Abreu, M.C. ; Baglin, C. ; Baldit, A. ; et al.
Phys.Lett.B 444 (1998) 516-522, 1998.
Inspire Record 478387 DOI 10.17182/hepdata.49294

Absolute J/ ψ and ψ ′ production cross sections have been measured at the CERN SPS, with 450 GeV/ c protons incident on a set of C, Al, Cu and W targets. Complementing these values with the results obtained by experiment NA51, which used the same beam and detector with H and D targets, we establish a coherent picture of charmonia production in proton-induced reactions at SPS energies. In particular, we show that the scaling of the J/ ψ cross section with the mass number of the target, A, is well described as A α , with α ψ =0.919±0.015. The ratio between the J/ ψ and ψ ′ yields, in our kinematical window, is found to be independent of A, with α ψ ′ − α ψ =0.014±0.011.

5 data tables

The ratio of the production cross sections, in the di-muon channel. Note that there are wo set of CU and WT data with targets of different lengths. An average values is also given for these.

The J/PSI absolute cross sections, times the BR to di-muons.

The PSI(3685) absolute cross sections, times the BR to di-muons.

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Muon pair and vector meson cross-sections in p W and S U collisions at 200-GeV/nucleon

The NA38 collaboration Abreu, M.C. ; Baglin, C. ; Baldisseri, A. ; et al.
Phys.Lett.B 368 (1996) 230-238, 1996.
Inspire Record 428066 DOI 10.17182/hepdata.28422

Muon pair production is studied in p - W and S  U collisions at 200 GeV per nucleon, as a function of transverse momentum P Tμμ . The inclusive ϱ + ω and Φ differential cross-sections dσ dP T are measured in the dimuon decay channel, for P T ≥ 0.6 GeV/c, in the central rapidity region, 3.0≤ y ≤ 4.0. Assuming the power law A-dependence σ = σ 0 ( A beam · A target ) α , the study of the integrated cross-sections for p - W and S  U collisions leads to α ϱ + ω = 1.00±0.02±0.07 and α Φ = 1.23±0.03±0.05, showing clear evidence of Φ enhancement in S  U interactions as compared to p - W collisions.

4 data tables

Statistical errors only.

Statistical errors only.

Statistical errors only.

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The Evolution of cross-section ratio psi-prime / J / psi from p A to S U interactions: Direct photon emission in correlation with Phi and J / psi

The NA38 collaboration Abreu, M.C. ; Baglin, C. ; Baldit, A. ; et al.
Nucl.Phys.A 590 (1995) 117C-126C, 1995.
Inspire Record 407649 DOI 10.17182/hepdata.42431

J ψ and ψ′ production cross sections are studied for several proton induced reactions and in SU collisions, in the NA38 experiment, by measuring the resonances' decays in the muon pair channel. Whereas in p-A interactions the ψ ′/ J / ψ ratio remains constantin going from p-p and p-d collisions to p-W and p-U, with a mean value of 1.76% ± 0.04%, in the SU data it exhibits half of this value and decreases as centrality of the collision increases. Also studied are the differences between the γ π 0 ratio yields correlated with the J ψ mass range and other dimuon masses; no significant effect is seen.

3 data tables

DATA IN THE COLLINS-SOPPER FRAME, OF -0.5<COS(THETA)<0.5.

DATA IN THE COLLINS-SOPPER FRAME, OF -0.5<COS(THETA)<0.5.

No description provided.


psi-Prime and J / psi production in p W, p U and S U interactions at 200-GeV/nucleon

The NA38 collaboration Baglin, C. ; Bussière, A. ; Guillaud, J.P. ; et al.
Phys.Lett.B 345 (1995) 617-621, 1995.
Inspire Record 387018 DOI 10.17182/hepdata.36562

Ψ′ and J/Ψ yields are compared in p-W, p-U and S-U interactions at 200 GeV/nucleon. Their ratio decreases from proton-t to sulphur-induced reactions. It also decreases in sulphur-induced reactions from peripheral to central collisions. This result could indicate that the Ψ′ and J/Ψ suppression mechanisms have different origins in p- and S-induced reactions.

3 data tables

No description provided.

No description provided.

No description provided.


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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Meson production in p + U, O + U and S + U interactions at 200-GeV/nucleon.

The NA38 collaboration Abreu, M.C. ; Baglin, C. ; Baldisseri, A. ; et al.
Z.Phys.C 55 (1992) 365-371, 1992.
Inspire Record 344266 DOI 10.17182/hepdata.14583

Meson production in proton, oxygen and sulphur interactions with uranium targets at 200 GeV/nucleon is studied. We measure the inclusive meson cross-section d σ/dPT2 and its evolution fromp+U to S+U. The cross-section fitted with an exponential gives an inverse slopePT0 of the order of 210 MeV/c. As a function of the neutral transverse energy,PT0 values show a slight rise followed by a plateau. The normalized difference (σ+−σ−)/σ− between positive and negative meson cross-sections is found to increase withET.

6 data tables

No description provided.

No description provided.

No description provided.

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Transverse momentum of J / psi produced in p Cu, p U, O-16 Cu, O-16 U and S-32 U collisions at 200-GeV per nucleon.

The NA38 collaboration Baglin, C. ; Baldisseri, A. ; Bussiere, A. ; et al.
Phys.Lett.B 262 (1991) 362-368, 1991.
Inspire Record 321322 DOI 10.17182/hepdata.29390

None

8 data tables

No description provided.

CONTINUUM MUONS ORIGINATE MAINLY FROM VECTOR MESON DECAYS, SEMI-LEPTONIC DECAYS OF D DBAR PAIRS AND FROM DRELL-YAN MECHANISM.

No description provided.

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Transverse momentum of dimuons production in p U, O U and S U collisions at 200-GeV/nucleon.

The NA38 collaboration Abreu, M.C. ; Alimi, M. ; Baglin, C. ; et al.
Nucl.Phys.A 525 (1991) 469C-472C, 1991.
Inspire Record 328922 DOI 10.17182/hepdata.36783

Dimuon production m p-U, O-U and S-U collisions has been studied at 200 GeV/N. It is observed that 〈 p T 〉 and 〈 p 2 T 〉 of the J / Ψ transverse momentum distributions increase with the transverse energy of the ion induced reactions. Such a marked behaviour is not seen for muon pairs of the continuum.

4 data tables

No description provided.

No description provided.

No description provided.

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Phi, rho, and omega production in p U, O U and S U reactions at 200-GeV per nucleon

The NA38 collaboration Baglin, C. ; Baldisseri, A. ; Bussiere, A. ; et al.
Phys.Lett.B 272 (1991) 449-454, 1991.
Inspire Record 325656 DOI 10.17182/hepdata.29289

Low mass muon pair production at high P T and low X F studied in pU, OU and SU 200 GeV per nucleon react ions. When energy density or projectile mass are increased, φ production is enhanced as compared with the yield of muon pairs in the mass continuum (1.7< M μμ < 2.4 GeV/ c 2 ), whereas the production of ω and ϱ, experimentally unresolved, remains approximately constant. This φ enhancement is in agreement with predictions based on quark-gluon plasma formation and, together with the previously reported J/Ψ suppression, puts severe constraints on a purely hadronic description of nucleus-nucleus collisions.

1 data table

The cross sections are parametrized as A**POWER.