Alexopoulos, T.
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$D$ Meson Production From 400 GeV/$c p p$ Interactions

The LEBC-EHS collaboration Aguilar-Benitez, M. ; Allison, W.W.M. ; Bailly, J.L. ; et al.
Phys.Lett.B 189 (1987) 476, 1987.
Inspire Record 245101 DOI 10.17182/hepdata.12913

We have measured the inclusive production properties of D and D messons produced from pp interactions at s =27.4 GeV . The differential production cross section is well represented by the empirical form d 2 σ d x F d P 2 T = 1 2 [σ ( D / D )(n+1)b](1−|x F |) n exp (−bp 2 T ) with n=4.9 ± 0.5, b=(1.0±0.1)( GeV /c) −2 , and the inclusive D / D cross section σ ( D / D ) is (30.2±3.3) ωb. The QCD fusion model predicts D / D production which is in good agreement with our data except for the magnitude of the cross section which depends sensitively on the assumed mass of the charm quark.

11 data tables
Table 1

No description provided.

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Study of the Reaction $\bar{p} p \to \bar{\Lambda} \Lambda$ Near Threshold

Barnes, P.D. ; Besold, R. ; Birien, P. ; et al.
Phys.Lett.B 189 (1987) 249-253, 1987.
Inspire Record 244883 DOI 10.17182/hepdata.30178

Results are presented from a study of the reaction p p→ Λ Λ near threshold. Over 3000 events recorded at s values 14.6 and 25.5 MeV above the Λ Λ threshold (2231.2 MeV) have been analysed. Results for the production cross section, differential cross section, and the Λ and Λ polarization are given at both energies and are compared with recent theoretical calculations of this process.

3 data tables
Table 1

Statistical errors only.

Table 2

No description provided.

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THE STUDY OF THE DIFFRACTION PROCESSES IN THE anti-p p ---> anti-p p pi+ pi- pi0 REACTION AT 22.4-GeV/c

The Alma Ata-Dubna-Moscow-Prague-Sofiya-Helsinki collaboration Batyunya, B.V. ; Boguslavsky, I.V. ; Bruncko, D. ; et al.
Sov.J.Nucl.Phys. 47 (1988) 261, 1988.
Inspire Record 247861 DOI 10.17182/hepdata.38866

None

2 data tables
Table 1

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Measurement of the Structure Functions F2 and Xf3 and Comparison With {QCD} Predictions Including Kinematical and Dynamical Higher Twist Effects

The BEBC WA59 collaboration Varvell, K. ; Cooper-Sarkar, A.M. ; Parker, M.A. ; et al.
Z.Phys.C 36 (1987) 1, 1987.
Inspire Record 245094 DOI 10.17182/hepdata.15775

The isoscalar nucleon structure functionsF2(x, Q2) andxF3(x, Q2) are measured in the range 0<Q2<64 GeV2, 1.7<W2<250 GeV2,x<0.7 using ν and\(\bar v\) interactions on neon in BEBC. The data are used to evaluate possible higher twist contributions and to determine their impact on the evaluation of the QCD parameter Λ. In contrast to previous analyses reaching to such lowW2 values, it is found that a low\(\Lambda _{\overline {MS} } \) value in the neighbourhood of 100 MeV describes the data adequately and that the contribution of dynamical higher twist effects is small and negative.

9 data tables
Table 1

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Analysis of Transverse Momentum Distributions for $p p$ Interactions at 360-{GeV}/$c$ in the Framework of a Quark - Diquark Fragmentation Model

The EHS-RCBC collaboration Bailly, J.L. ; Bruyant, F. ; Buschbeck, B. ; et al.
Z.Phys.C 35 (1987) 295, 1987.
Inspire Record 245106 DOI 10.17182/hepdata.15802

Using a quark-diquark fragmentation model, in which either the Field-Feynman or the Lund model is coupled with a quark-diquark distribution function, we study transverse momentum distributions,pT, for the inclusive reactionspp→hadron +anything at 360 GeV/c. We find that a primordial mean transverse momentum 〈kT〉≃0.4 GeV/c can well reproduce thepT2 distributions of charged hadrons, π0,Ks0, Λ0,K* and Σ* and the Feynmanx−pT correlations. We confirm that a diquark in a proton plays an important rôle in reproducing thex−pT correlation of Λ0.

1 data table
Table 1

No description provided.


rivet Analysis
Observation of $e^+ e^- \to D(s$)+- $D^*(s$)-+ at $\sqrt{s}=4$.14-{GeV}

The MARK-III collaboration Blaylock, G. ; Bolton, T. ; Brown, J.S. ; et al.
Phys.Rev.Lett. 58 (1987) 2171, 1987.
Inspire Record 244856 DOI 10.17182/hepdata.20170

We present evidence for the exclusive reaction e+e−→Ds±Ds*∓, observed with the Mark III detector at the SLAC storage ring SPEAR. The Ds± is reconstructed in the φπ± decay mode, while the Ds*∓ is detected as a narrow peak in the recoil-mass distribution. The mass of the Ds* is found to be 2109.3±2.1±3.1 MeV/c2, yielding a Ds*−Ds mass difference of 137.9±2.1±4.3 MeV/c2. The width of the Ds* is <22 MeV/c2 at the 90%-confidence level. The observed signal corresponds to σ(e+e−→Ds+Ds*−+Ds−Ds*+)B(Ds+→φπ+)=30±6±11 pb at s=4.14 GeV.

1 data table
Table 1

No description provided.


Inclusive Pion Production in 360-{GeV}/$c p p$ Interactions

The EHS-RCBC collaboration Bailly, J.L. ; Bartl, W. ; Buschbeck, B. ; et al.
Z.Phys.C 35 (1987) 309, 1987.
Inspire Record 245413 DOI 10.17182/hepdata.17437

In a study of proton-proton interactions at\(\sqrt s= 26GeV\), inclusive distributions of single pions and systems of pions of various charge combinations are presented, as well as the production ratio obtained in association with various trigger particles. The results are compared to current phenomenological models in an attempt to understand multiparticle productions in hadron collisions.

1 data table

Multiplicity, Momentum and Angular Distributions of Protons From the Interactions of $P$, $D$, $\alpha$ and C With Carbon at 4.2-{GeV}/c/nucleon Momentum. Alma-ata-baku-belgrade-bucharest-cracow-dubna-kishinev-leipzig- Moscow-prague-samarkand-sofia-tashkent-tbili

Armutliiski, D. ; Bogdanovic, J. ; Didenko, L.A. ; et al.
Z.Phys.A 328 (1987) 455-461, 1987.
Inspire Record 255393 DOI 10.17182/hepdata.9501

None

17 data tables
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No description provided.

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Strangeness Suppression and Inclusive $\phi$ and $K^*$0 Production in $K^+ P$ Interactions at 250-{GeV}/c

The EHS - NA22 collaboration Adamus, M. ; Agababyan, N.M. ; Ajinenko, I.V. ; et al.
Phys.Lett.B 198 (1987) 427-432, 1987.
Inspire Record 254217 DOI 10.17182/hepdata.30075

We present inclusive ¶ and K *0 (892) cross sections and Feynman x -spectra in K + p collisions at 250 GeV/ c . In the K + fragmentation region, x > 0.2, the ratio of ¶ to K *0 (892) is used to estimate the strangeness suppression factor λ , with the result γ =0.17 ± 0.02 (stat ± 0.01 (syst). We see no evidence for an energy dependence of λ in the CM energy range 7.8 ≤ s ≤21.7 GeV.

4 data tables
Table 1

RESULTS AT 32 AND 70 GEV INCLUDED FOR COMPARISON.

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RESULTS AT 32 AND 70 GEV INCLUDED FOR COMPARISON.

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RESULTS AT 32 AND 70 GEV INCLUDED FOR COMPARISON.

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The Production of Prompt Positrons at Low Transverse Momentum Increases With the Square of the Associated Charged Multiplicity

The Axial Field Spectrometer collaboration Åkesson, T. ; Albrow, M.G. ; Almehed, S. ; et al.
Phys.Lett.B 192 (1987) 463-470, 1987.
Inspire Record 244887 DOI 10.17182/hepdata.30156

We have measured the production of prompt positrons in pp collisions at √ s = 63 GeV and y = 0 in the p T interval 0.12< p T <1.0 GeV/c. The results indicate that the production of positrons at low p T (<0.4 GeV/ c ) is proportional to the square of the mean multiplicity in the central region | y | < 1. Such a quadratic dependence is not expected from final-state sources such as hadronic bremsstrahlung or hadronic decays, but is natural in models where low mass electron pairs are produced by interactions of constituents created during the collision.

3 data tables
Table 1

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