Date

Determination of $alpha_{s}$ in second order {QCD} from hadronic $Z$ decays

The DELPHI collaboration Abreu, P. ; Adam, W. ; Adami, F. ; et al.
Z.Phys.C 54 (1992) 55-74, 1992.
Inspire Record 333272 DOI 10.17182/hepdata.14603

Distributions of event shape variables obtained from 120600 hadronicZ decays measured with the DELPHI detector are compared to the predictions of QCD based event generators. Values of the strong coupling constant αs are derived as a function of the renormalization scale from a quantitative analysis of eight hadronic distributions. The final result, αs(MZ), is based on second order perturbation theory and uses two hadronization corrections, one computed with a parton shower model and the other with a QCD matrix element model.

9 data tables

Experimental differential Thrust distributions.

Experimental differential Oblateness distributions.

Experimental differential C-parameter distributions.

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PHOTON DIFFRACTIVE DISSOCIATION TO rho rho pi AND rho pi pi pi STATES

The Omega Photon collaboration Atkinson, M. ; Axon, T.J. ; Barberis, D. ; et al.
Z.Phys.C 38 (1988) 535, 1988.
Inspire Record 261249 DOI 10.17182/hepdata.48824

This paper reports studies of the reactions γp→ρ π π πp and γp→ρ ρ πp. In particular a peak is reported in the ρ ρ π mass spectrum with closely similar mass and width to those of the ω ρ π peak previously reported in the reaction γp→ω ρ πp. The ratio of production cross sections is found to be ρ ρ π/ω ρ π=0.96±0.19, in serious disagreement with the expectation from Vector Meson Dominance. A possible explanation is indicated.

2 data tables

No description provided.

Numerical values requested from authors.


Study of $\eta \pi^+ \pi^-$ States in the $\rho^\prime$ (1600) Mass Region Photoproduced in the Reaction $\gamma p \to \eta \pi^+ \pi^- p$ at Photon Energies of 20-{GeV} to 70-{GeV}

The Omega Photon collaboration Atkinson, M. ; Axon, T.J. ; Barberis, D. ; et al.
Z.Phys.C 30 (1986) 531, 1986.
Inspire Record 218611 DOI 10.17182/hepdata.15991

In diffractive photoproduction ofηπ+π−, the two-body substatesηρ0 andA2π are found to contribute significantly to the cross-section forηπ+π− masses below 2.4 GeV. From a spin-parity analysis the branching ratio, ρ′(1600)→ηρ/ρ′(1600)→, is determined to be <0.02 at the 68.3% confidence level. TheA2π component shows an enhancement around 1.7 GeV. The spin-parity analysis indicates a probable contribution to this signal from exclusive photoproduction of theg(1690).

6 data tables

No description provided.

Not corrected for 35% background under the eta --> gamma gamma peak.

Not corrected for 35% background under the ETA --> GAMMA GAMMA peak.

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Observation of a Narrow K anti-K State in J/psi Radiative Decays

The MARK-III collaboration Baltrusaitis, R.M. ; Becker, J. ; Blaylock, G. ; et al.
Phys.Rev.Lett. 56 (1986) 107, 1986.
Inspire Record 217856 DOI 10.17182/hepdata.20254

Evidence is presented for a narrow state, called ξ, in the decay modes J/ψ→γξ, ξ→K+K−, and ξ→KS0KS0. In the K+K− mode, the ξ has a mass of 2.230±0.006±0.014 GeV/c2, a width of Γ=0.026−0.016+0.020± 0.017 GeV/c2, a product branching ratio of (4.2−1.4+1.7±0.8)×10 −5, and a statistical significance of ∼4.5 standard deviations. In the KS0KS0 mode, it has a mass of 2.232±0.007±0.007 GeV/c2, a width of Γ=0.018−0.015+0.023± 0.010 GeV/c2, a product branching ratio of (3.1−1.3+1.6±0.7)×10 −5, and a statistical significance of ∼3.6 standard deviations. Limits on ξ decay to other final states are presented.

1 data table

No description provided.


Measurement of the Radiative Width of the $\eta^\prime$ (958) in Two Photon Interactions

The TASSO collaboration Althoff, M. ; Braunschweig, W. ; Kirschfink, F.J. ; et al.
Phys.Lett.B 147 (1984) 487-492, 1984.
Inspire Record 203795 DOI 10.17182/hepdata.30481

The reaction e + e − →e + e − η ′(958) has been observed by detecting the final state π + π − γ . The two-photon width of the η′ has been measured to be Γ ( η ′→ γγ ) = 5.1±0.4±0.7 keV. A search for the ι (1440) has been made in the ϱ 0 γ final state. An upper limit has been obtained for the product Γ ( ι (1440) → γ ) gg ), B ( ι → ϱ 0 γ ) < 1.5 keV (95%CL).

1 data table

No description provided.


Photoproduction of $K \bar{K} \pi$ Final States in the Photon Energy Range From 20-{GeV} to 70-{GeV}

The Omega Photon collaboration Atkinson, M. ; Axon, T.J. ; Barberis, D. ; et al.
Nucl.Phys.B 231 (1984) 1-14, 1984.
Inspire Record 191239 DOI 10.17182/hepdata.33920

The reactions γ p→K + K − π 0 (p) and γ p→ K s 0 K ± π ± (p) have been measured using tagged photons in the energy range 20 to 70 GeV. No resonance structure is observed in either of the K K π invariant mass distributions, which range from threshold up to ∼ 3 GeV. The photoproduction cross sections for φπ 0 and K ∗ (892)K are presented and are compared with theoretical predictions. No evidence has been found for the photoproduction of φ′ (1680).

3 data tables

No description provided.

No description provided.

NO EVIDENCE FOR RESONANT STRUCTURE AT PHIPRIME(1680).


Study of Inclusive Production of Boson Resonances in $\bar{p} p$ Interactions at 32-{GeV}/$c$

The French-Soviet & CERN-Soviet collaborations Starchenko, E.A. ; Chekulaev, S.V. ; Galyaev, N.A. ; et al.
Z.Phys.C 16 (1983) 181, 1983.
Inspire Record 168177 DOI 10.17182/hepdata.22268

The inclusive production ofK*±(890), ρρ(770), ω0(780) andf0(1,270) mesons is studied in\(\bar pp\) experiment at 32GeV/c in the MIRABELLE bubble chamber by the analysis of (K0π±) and (π+π−) invariant mass distributions. The inclusive cross sections are σ(K*±)=2.45±0.30 mb, σ(ρ0)=8.8 ±0.9 mb, σ(ω+)≃6.2 mb, and σ(f0)=2.2±0.7 mb. The C.M. longitudinal distribution of theK*±(890) is slightly shifted to the primary particles fragmentation regions; the ρ0 is produced more centrally. The studied mesons alone are responsible for 40% of final state poins. The production features of various resonances are compared with quark models predictions.

13 data tables

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Inclusive $K^{*+}$(1430), $K^{*0}$(1430) and $F(1270)$ Production in $K^+ p$ Interactions at 32-{GeV}/$c$

Chliapnikov, P.V. ; Falaleev, V.P. ; Gerdyukov, L.N. ; et al.
Z.Phys.C 12 (1982) 113, 1982.
Inspire Record 167340 DOI 10.17182/hepdata.10914

Results are presented on total and semiinclusive cross sections, longitudinal and transverse momentum distributions of the tensor mesonsK*+(1430),K*0(1430), andf(1270) observed inK+p interactions at 32 GeV/c. The data are compared withK*+(892).K*0(896) and ϱ0 vector meson production in the same experiment. The shapes of inclusive invariantx-spectra for the strange vector and tensor mesons are found to be rather similar, after removal of diffractive and quasi-two-body channels, in agreement with quark-recombination ideas.

21 data tables

MULT FOR THE TENSOR MESONS CALCULATED AS MULT=SIG(RES)/SIG(N<=8), WHERE SIG(N<=8) IS THE SUM OF TOPOLOGICAL CROSS SECTIONS WITH N <= 8.

No description provided.

No description provided.

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GENERAL FEATURES AND CLUSTER - LIKE PROPERTIES OF REACTION K+ p ---> K+ p 2 pi+ 2 pi- AT 32-GeV/c

Azhinenko, I.V. ; Belokopytov, Yu.A. ; Chliapnikov, P.V. ; et al.
Sov.J.Nucl.Phys. 34 (1981) 584, 1981.
Inspire Record 165495 DOI 10.17182/hepdata.10705

None

58 data tables

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Inclusive Production of $\Delta^{++}$(1232) and $\Sigma^\pm$(1385) in $K^+ p$ Interactions at 32-{GeV}/$c$

The Soviet-CERN collaboration Azhinenko, I.V. ; Barth, M. ; Belokopytov, Yu.A. ; et al.
IFVE-80-129, 1980.
Inspire Record 156508 DOI 10.17182/hepdata.41431

None

9 data tables

No description provided.

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