Hadjidakis, C.
POWER
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Electron positron pair production in Coulomb collisions of ultrarelativistic sulphur ions with fixed targets

Vane, C.R. ; Datz, S. ; Dittner, P.F. ; et al.
Phys.Rev.Lett. 69 (1992) 1911-1914, 1992.
Inspire Record 343889 DOI 10.17182/hepdata.19818

Angular and momentum distributions have been measured for positrons from electron-positron pairs created in peripheral collisions of 6.4-TeV sulfur ions with fixed targets of Al, Pd, and Au. The data are compared with results of several theoretical treatments. Measured differential cross sections peak at low momentum (≤1 MeV/c), extend significantly to much higher momenta (>17 MeV/c), and concentrate sharply in the forward direction, along the ion-beam axis. Positron yields scale as the square of the target nuclear charge as predicted by theory.

1 data table
Table 1

No description provided.


Charm Meson Production in 800-GeV/c Proton - Emulsion Interactions

The Fermilab E653 collaboration Kodama, K. ; Ushida, N. ; Mokhtarani, A. ; et al.
Phys.Lett.B 263 (1991) 573-578, 1991.
Inspire Record 30879 DOI 10.17182/hepdata.47110

We report results on D 0 and D + production in proton-emulsion interactions at s =38.7 GeV. A fit to the form (1−| x F |) n exp (−bp 2 T ) yields n=6.9 +1.9 −1.8 and b=0.84 +0.10 −0.08 (GeV/ c ) −2 . The total inclusive cross section, is assuming linear A dependence, is measured to be 38±3(stat.) ±13 (sys.) μ b for the D 0 and 38±9±14 μ b for the D + . A comparison of these results with previous measurements indicates that nuclear effects do not strongly influence charm production. The predictions of QCD are in good agreement with our data.

3 data tables
Table 1

The differential cross section is fitted by the equation : D2(SIG)/D(XL)/D(PT**2) = CONST*(1-XL)**POWER*EXP(-SLOPE*PT**2).

Table 2

The differential cross section is fitted by the equation : D2(SIG)/D(XL)/D(PT**2) = CONST*(1-XL)**POWER*EXP(-SLOPE*PT**2).

Table 3

Linear A-dependence. Different modes of the charm mesons detection were used (see text for detail).


{$J/\psi$} and muon-pair cross-sections in proton-nucleus and nucleus-nucleus collisions at 200 GeV per nucleon

Baglin, C. ; Baldisseri, A. ; Bussiere, A. ; et al.
Phys.Lett.B 270 (1991) 105-110, 1991.
Inspire Record 328409 DOI 10.17182/hepdata.29301

Muon-pair production has been measured in pCu, pU, OCu, OU and SU collisions at 200 GeV per nucleon. The cross sections are compatible with the atomic number dependence ( A proj. A targ. ) α where α =0.91±0.04 for the J/ψ resonance and α =1.01±0.04 for muon pairs produced in the mass continuum between 1.7 and 2.7 GeV/ c 2 .

10 data tables
Table 1

Cross sections fitted with SIG0*(A(P=1)*A(P=2))** ALPHA. ALPHA is coded here as POWER(N=A*A,YN=SIG).

Table 2

Cross sections fitted with SIG0*(A(P=1)*A(P=2))** ALPHA. ALPHA is coded here as POWER(N=A*A,YN=SIG).

Table 3

No description provided.

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Hadroproduction of D anti-D pairs in the interaction of 350-GeV/c pi- mesons with nuclei

The WA75 collaboration Aoki, S. ; Baroni, G. ; Bisi, V. ; et al.
Prog.Theor.Phys. 87 (1992) 1315-1322, 1992.
Inspire Record 322545 DOI 10.17182/hepdata.48517

Results are presented on the production characteristics of charmed particles obtained from the WA75 emulsion hybrid experiment. The events, selected by the presence of a muon with a high momentum transverse to the beam direction, were located and analysed in nuclear emulsions. Inclusive and correlation properties are systematically compared with the lowest-order QCD calculations for DD hadroproduction. Results concerning the correlation properties indicate some contribution from next-to-leading order [O(α_S^3)] subprocesses.

5 data tables
Table 1

459 DECAYS: 119 D0, 119 DBAR0, 115 D+, 106 D-.

Table 2

177 PAIRS: 38 D0 DBAR0, 46 D0 D-, 45 D+ DBAR0, 48 D+ D-.

Table 3

120 PAIRS: 38 D0 DBAR0, 31 D0 D-, 32 D+ DBAR0, 19 D+ D-.

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Production of $\pi^0$ Mesons at high $p_T$ in $\pi^-$Be and pBe Collisions at 500 GeV/c

Alverson, G. ; Baker, W.F. ; Ballocchi, G. ; et al.
Phys.Rev.D 45 (1992) R3899-R3902, 1992.
Inspire Record 318740 DOI 10.17182/hepdata.22751

We present new measurements of π0 production at high transverse momenta (pT) for π− and p interactions on Be and Cu targets at 500 GeV/c. The observed dependence of the yields as a function of pT and rapidity (y) is compared with expectations from leading-log QCD over a kinematic range in which the inclusive cross sections fall by more than 4 order of magnitude.

2 data tables
Table 1

No description provided.

Table 2

A dependence parameterized as A**POWER for both Pi- and P interactions.


Nuclear dependence of the production of Upsilon resonances at 800-GeV

Alde, D.M. ; Baer, H.W. ; Carey, T.A. ; et al.
Phys.Rev.Lett. 66 (1991) 2285-2288, 1991.
Inspire Record 315062 DOI 10.17182/hepdata.19910

The yields of the 1S and the sum of the 2S and 3S Υ resonances have been measured for 800-GeV protons incident on targets of H2, C, Ca, Fe, and W. A significant nuclear dependence is seen in the yield per nucleon which, within errors, is the same for the Υ(1S) and Υ(2S+3D) states. A large decrease in the relative yield from heavy nuclei is found for the range xF<0. Significant nuclear dependence is also observed in the pt distribution. Differential cross sections for the Υ(1S) for H2 are presented over the ranges 0.24≤pt≤3.4 GeV/c and -0.15≤xF≤0.5.

8 data tables
Table 1

Mass dependence as a function of feynman X for UPSI(1S) production.

Table 2

Mass dependence as a function of feynman X for UPSI(2S/3S) production.

Table 3

Mass dependence as a function of transverse momentum for UPSI(1S) production.

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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
Table 1

The cross sections are parametrized as A**POWER.


A Search for weakly interacting neutral particles in missing energy events in 450-GeV/c p N collisions

The HELIOS collaboration Åkesson, T. ; Almehed, S. ; Angelis, A.L. S. ; et al.
Z.Phys.C 52 (1991) 219-226, 1991.
Inspire Record 302922 DOI 10.17182/hepdata.15014

We have measured the inclusive cross-section as a function of missing energy, due to the production of neutrinos or new weakly interacting neutral particles in 450 GeV/c proton-nucleus collisions, using calorimetric measurements of visible event energy. Upper limits are placed on the production of new particles as a function of their energy. These upper limits are typically an order

9 data tables
Table 1

Differential single diffraction cross section.

Table 2

Differential single diffraction cross section.

Table 3

Differential single diffraction cross section.

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The A-Dependence of $J / \psi$ and $\psi^{\prime}$ Production at 800 GeV/c

Alde, D.M. ; Baer, H.W. ; Carey, T.A. ; et al.
Phys.Rev.Lett. 66 (1991) 133-136, 1991.
Inspire Record 301531 DOI 10.17182/hepdata.19916

The yield of J/ψ and ψ’ vector-meson states has been measured for 800-GeV protons incident on deuterium, carbon, calcium, iron, and tungsten targets. A depletion of the yield per nucleon from heavy nuclei is observed for both J/ψ and ψ’ production. This depletion exhibits a strong dependence on xF and pt. Within experimental errors the depletion is the same for the J/ψ and the ψ’.

13 data tables
Table 1

Ratio of heavy nucleus to deuterium yields. A is the mass number of the target nucleus.

Table 2

Ratio of heavy nucleus to deuterium yeilds. A is the mass number of the target nucleus.

Table 3

Ratio of heavy nucleus to deuterium yeilds. A is the mass number of the target nucleus.

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Atomic Weight Dependence of the Production of Hadron Pairs from 800-GeV/c Protons on Nuclear Targets

Turner, Kathleen R. ; Boca, G. ; Georgiopoulos, C. ; et al.
Phys.Rev.Lett. 66 (1991) 864-867, 1991.
Inspire Record 278395 DOI 10.17182/hepdata.19892

Fermilab experiment 711 has investigated proton-nucleus collisions in which two high-transverse-momentum hadrons are produced forming high-mass ++, +-, and -- charged states, using an 800-GeV/c proton beam on targets of beryllium, aluminum, iron, and tungsten. Our data cover the range in dihadron mass from 6 to 15 GeV/c2. We show here that the dependence of the cross section on atomic weight A can be parametrized as Aα where α=1.043±0.011(stat)±0.025 (syst), and is independent of the charge state of the dihadron system.

3 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.