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Charged Particle Multiplicity Distributions in Oxygen - Nucleus Collisions at 60-{GeV} and 200-{GeV} Per Nucleon

The HELIOS collaboration Akesson, T. ; Almehed, S. ; Angelis, A.L.S. ; et al.

Nucl.Phys.B 333 (1990) 48-65, 1990.

Inspire Record 281287 DOI 10.17182/hepdata.33112

Multiplicity distributions of charged particles produced in the pseudorapidity range 0.9 < η lab < 5.5 were measured in oxygen-nucleus collisions for Al, Ag, and W target nuclei at incident energies of 60 and 200 GeV per nucleon. The multiplicity differential cross sections and the pseudorapidity distributions as a function of transverse energy are presented for the various target nuclei. The correlation between charged multiplicity and transverse energy is studied as a function of transverse energy. Data are compared with predictions of the IRIS and FRITIOF generators.

18 data tables

Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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Inclusive Negative Particle $p(T$) Spectra in $P$ - Nucleus and Nucleus-nucleus Collisions at 200-{GeV} Per Nucleon

The Helios collaboration Åkesson, T. ; Almehed, S. ; Angelis, A.L. S. ; et al.

Z.Phys.C 46 (1990) 361-368, 1990.

Inspire Record 282897 DOI 10.17182/hepdata.15239

The HELIOS experiment has measured inclusivep⊥ spectra of negative particles in the rapidity region 1.0<y<1.9. The general shape of thep⊥ spectra in p +W, O+W and S+W is similar, but cannot be described by a single exponential. Compared to p+p collisions, an excess is observed for low and highp⊥. This effect increases with the projectile mass. Except for very lowE⊥, the average transverse momentum <p⊥> is found to be approximately constant up to the highest accessible values ofE⊥.

3 data tables

Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

First Measurements of Hadronic Decays of the $Z$ Boson

The MARK-II collaboration Abrams, G.S. ; Adolphsen, Chris ; Aleksan, R. ; et al.

Phys.Rev.Lett. 63 (1989) 1558, 1989.

Inspire Record 282670 DOI 10.17182/hepdata.20044

We have observed hadronic final states produced in the decays of Z bosons. In order to study the parton structure of these events, we compare the distributions in sphericity, thurst, aplanarity, and number of jets to the predictions of several QCD-based models and to data from lower energies. The data and models agree within the present statistical precision.

5 data tables

Table 1

Corrected event shape distributions.

Table 2

Corrected event shape distributions.

Table 3

Corrected event shape distributions.

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rivet Analysis
Measurements of $\alpha^- s$ in $e^+ e^-$ Annihilation at $\sqrt{s}=53$.3-{GeV} and 59.5-{GeV}

The TOPAZ collaboration Adachi, I. ; Aihara, H. ; Doser, M. ; et al.

Phys.Lett.B 227 (1989) 495-500, 1989.

Inspire Record 279575 DOI 10.17182/hepdata.29800

We studied the energy-energy correlation (EEC) and its asymmetry (AEEC) using e + e − hadronic annihilation events obtained at √ s =53.3 GeV and 59.5 GeV with the TOPAZ detector at the TRISTAN collider. We used a Monte Carlo simulation combined with the QCD matrix elements by Gottschalk and Shatz and the Lund string fragmentation model. By comparing the experimental data with simulated events, we determined the strong coupling constant α s at both energies. The results are 0.129±0.007 (stat) ±0.010 (syst) at √ s =53.3 GeV and 0.122±0.008 (stat) ±0.010 (syst) at 59.5 GeV.

2 data tables

Table 1

No description provided.

Table 2

No description provided.

rivet Analysis
Inclusive $\pi^0$ and $\eta$ Meson Production in Electron Positron Interactions at $\sqrt{s}=10$-{GeV}

The ARGUS collaboration Albrecht, H. ; Glaser, R. ; Harder, G. ; et al.

Z.Phys.C 46 (1990) 15, 1990.

Inspire Record 278933 DOI 10.17182/hepdata.15301

We report on a high statistics study of π0 and η production in continuum events and in direct decays of the Γ(1S) and Γ(2S) resonances. The measured production rates per event are$\left\langle {n_{\pi ^0 } } \right\rangle$=3.22 ± 0.07 ± 0.31 (3.97 ± 0.23 ± 0.38) and 〈nη〉=0.19 ± 0.04 ± 0.04 (0.40 ± 0.14 ± 0.09) for continuum events (direct Γ(1S) decays).

6 data tables

Table 1

First data point in table is from the continuum at sqrt(s)=9.46 GeV.

Table 2

First data point in table is from the continuum at sqrt(s)=9.46 GeV.

Table 3

PI0 spectrum in the continuum.

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rivet Analysis
Production and Decay of Charmed Mesons in $e^+ e^-$ Annihilation at $\sqrt{s}$ > 28-{GeV}

The TASSO collaboration Braunschweig, W. ; Gerhards, R. ; Kirschfink, F.J. ; et al.

Z.Phys.C 44 (1989) 365, 1989.

Inspire Record 278856 DOI 10.17182/hepdata.15361

We report on a study of inclusive production ofD*± mesons ine+e− annihilation at c.m. energies between 28 and 46.8 GeV using the TASSO detector at the PETRA storage ring. A hardD*± energy spectrum is measured with a maximum nearED*±≃0.6Ebeam. The measured cross section ratio$(\sigma _{D^{* + } }+ \sigma _{D^{* - } } )/\sigma _{\mu \mu }= 1.28 \pm 0.09 \pm 0.18$ indicates thatD* production accounts for a large fraction of the observed charm production. Two complementary methods have been used to determine the forward-backward asymmetry of charm pair production due to electroweak interference. Combining both measurements the product of the axial vector couplings of the electron and the charm quark to the weak neutral current was determined to begAegAc=−(0.276±0.073), in agreement with the standard model prediction of −0.25. Using a sample of reconstructedD*± mesons, the relative strength of the strong interaction coupling of thec quark compared to that of an average of all flavours is measured as αs(c)/αs(all)=0.91±0.38±0.15, consistent with the coupling constant being flavour independent. An update of ourD0 lifetime measurement is presented, based on a considerable increase in statistics, the final result being$\tau _{D^0= } (4.8 \pm _{0.9 - 0.7}^{1.0 + 0.5} )10^{ - 13} s$.

5 data tables

Table 1

Cross sections using D0 --> K- PI+ channel.

Table 2

Cross sections using D0 --> K- PI+ PI- PI+ channel.

Table 3

No description provided.

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K0(S) PRODUCTION IN ANTI-P P INTERACTIONS AT S**(1/2) = 630-GeV AND 1800-GEV

The CDF collaboration Abe, F. ; Amidei, D. ; Apollinari, G. ; et al.

Phys.Rev.D 40 (1989) 3791-3794, 1989.

Inspire Record 287811 DOI 10.17182/hepdata.22999

Measurements of inclusive transverse-momentum spectra for KS0 mesons produced in proton-antiproton collisions at s of 630 and 1800 GeV are presented and compared with data taken at lower energies. The ratio, as a function of pT, of the cross section for KS0 to that for charged hadrons is very similar to what is observed at lower energies. At 1800 GeV, we calculate the strangeness-suppression factor λ=0.40±0.05.

4 data tables

Table 1

Estimated effective cross sections for events which pass the trigger and selection criteria. The uncertainties in these represent the principal source of error in the overall normalisation of the results.

Table 2

Statistical errors only.

Table 3

Statistical errors only.

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Experimental Evidence for the Nonabelian Nature of {QCD}

The AMY collaboration Park, I.H. ; Schnetzer, S. ; Green, J. ; et al.

Phys.Rev.Lett. 62 (1989) 1713, 1989.

Inspire Record 276619 DOI 10.17182/hepdata.20045

We present evidence for the non-Abelian nature of QCD from a study of multijet events produced in e+e− annihilations from √s =50 to 57 GeV in the AMY detector at the KEK storage ring TRISTAN. A comparison of the three-jet event fraction at TRISTAN to the fraction of the DESY storage ring PETRA shows that the QCD coupling strength αs decreases with increasing Q2. In addition, measurements of the angular distributions of four-jet events show evidence for the triple-gluon vertex.

2 data tables

Table 1

No description provided.

Table 2

No description provided.

Central Collisions of 800-{GeV} Protons With Ag / Br Nuclei in Nuclear Emulsion

The BATON ROUGE-KRAKOW-MOSCOW-TASHKENT collaboration Abduzhamilov, A. ; Barbier, L.M. ; Chernova, L.P. ; et al.

Phys.Rev.D 39 (1989) 86-91, 1989.

Inspire Record 280844 DOI 10.17182/hepdata.3813

Central collisions of 800-GeV protons with the heavy components of nuclear emulsion, Ag107 and Br80, have been investigated to determine the characteristics of small-impact-parameter collisions and, by comparison with the analysis of inclusive proton-emulsion inelastic interactions and inelastic proton-nucleon collisions, to study the dependence of the interaction process on the mean number of intranuclear collisions 〈ν〉. The data are also compared with the results obtained in proton-emulsion collisions, both central and inclusive, at 200 GeV. The variations in the secondary-particle multiplicities and the normalized pseudorapidity density correlate with 〈ν〉 and demonstrate that proton-nucleus interactions, both central and inclusive, can be described adequately by the incoherent superposition of proton-nucleon collisions.

5 data tables

Table 1

NUCLEUS IS AVERAGE NUCLEUS OF EMULSION.

Table 2

NUCLEUS IS AVERAGE NUCLEUS OF EMULSION.

Table 3

NUCLEUS IS AVERAGE NUCLEUS OF EMULSION.