Date

A Study of Energy-energy Correlations in $e^+ e^-$ Annihilations at $\sqrt{s}=34$.6-{GeV}

The PLUTO collaboration Berger, Christoph ; Genzel, H. ; Lackas, W. ; et al.
Z.Phys.C 28 (1985) 365, 1985.
Inspire Record 215869 DOI 10.17182/hepdata.16029

We present high statistics measurements of the energy-energy correlation (EEC) and its related asymmetry (AEEC) ine+e− annihilation at a c.m. energy of 34.6 GeV. We find that the energy dependence as well as the large angle behaviour of the latter are well described by perturbative QCD calculations toOα(s2). Non-perturbative effects are estimated with the help of fragmentation models in which different jet topologies are separated using (ɛ, δ) cuts, and found to be small. The extracted values of\(\Lambda _{\overline {MS} }\) lie between 100 and 300 MeV.

2 data tables

Corrected energy-energy correlation data.

CORRECTED FORWARD-BACKWARD ASYMMETRY.


A Measurement of the Total Cross-section and a Study of Inclusive Muon Production for the Process $e^+ e^- \to$ Hadrons in the Energy Range Between 39.79-{GeV} and 46.78-{GeV}

The JADE collaboration Bartel, W. ; Becker, L. ; Cords, D. ; et al.
Phys.Lett.B 160 (1985) 337-342, 1985.
Inspire Record 216799 DOI 10.17182/hepdata.30375

The total cross section and the inclusive muon cross section for the process e + e − → hadrons have been measured in the center of mass energy range between 39.79 and 46.78 GeV. The ratio R shows no significant structure. It has an average value of 4.13±0.08±0.14. An upper limit is set on the production of narrow resonances. Limits are obtained for pair-produced heavy quarks. The data are compared with the standard electroweak interaction model including QCD corrections taking into account the five known types of quarks. Upper limits are given for a possible structure of quarks and for effects of color octet leptons.

1 data table

Figure 1 also shows energy scan of 'R'.


Tau Lepton Production and Decay at {PETRA} Energies

The JADE collaboration Bartel, W. ; Becker, L. ; Cords, D. ; et al.
Phys.Lett.B 161 (1985) 188, 1985.
Inspire Record 220695 DOI 10.17182/hepdata.30350

The production and decay of τ-pairs was studied with the JADE detector at PETRA at center-of-mass energies of 30 ⩽√ s ⩽ 46.78 GeV. The total production cross section for τ-pairs agreed with QED predictions to order α 3 . Lower limits on QED cut-off parameters of Λ + > 285 GeV and Λ − > 210 GeV at 95% confidence level were ontained. The decay branching fractions into one and three charged particles were determined to be (86.1 ± 0.5 ± 0.9)% and (13.6±0.5 ±0.80)%. In the angular distributions a forward-backward asymmetry was observed, from which the axial-vector weak charge to the τ was determined to be a τ = −0.74 ± 0.22 in agreement with the standard model. An analysis of the process e + e − → τ + τ − γ showed agreement with QED calculations to O(α 3 ).

4 data tables

Includes data from earlier analysis at lower energy - M. Nozaki - Tokyo - UTLICEPP-82-02.

Angular distributions - data requested from authors.

Forward-backward asymmetry determined from fit to angular distribution of form N*(1 + cos(theta)**2 + (3/8)*A*cos(theta)).

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Study of the Reaction $\gamma \gamma \to 2 \pi^+ 2 \pi^- \pi^0$ and Upper Limits on the Production of $\gamma \gamma \to \omega \omega$ and $\gamma \gamma \to \rho^0 \omega$

The PLUTO collaboration Berger, Christoph ; Genzel, H. ; Lackas, W. ; et al.
Z.Phys.C 29 (1985) 183, 1985.
Inspire Record 220911 DOI 10.17182/hepdata.15911

A search for the reactionsγγ→ωω andγγ→ρ0ω has been carried out at an averagee+e− CM energy of 34.6 GeV with an integrated luminosity of 45 pb−1. Upper limits are set for these two channels over the γγ CM Energy range of 1.6 to 2.5 GeV. The cross section is determined for the exclusive channelγγ→π+2π−π0.

3 data tables

Data read from graph.

Data read from graph.

Data read from graph.


Search for Two Photon Production of Resonances Decaying Into $K \bar{K}$ and $K \bar{K} \pi$

The TASSO collaboration Althoff, M. ; Braunschweig, W. ; Kirschfink, F.J. ; et al.
Z.Phys.C 29 (1985) 189, 1985.
Inspire Record 220941 DOI 10.17182/hepdata.16018

An analysis of the production ofKS0KS0 andK±Ks0π∓ by two quasi-real photons is presented. The cross section forγγ→K0\(\overline {K^0 } \), which is given for the γγ invariant mass range fromK\(\bar K\) threshold to 2.5 GeV, is dominated by thef′(1525) resonance and an enhancement near theK\(\bar K\) threshold. Upper limits on the product of the two-photon width times the branching ratio intoK\(\bar K\) pairs are given forΘ(1700),h(2030), and ξ(2220). For exclusive two-photon production ofK±Ks0π∓ no significant signal was observed. Upper limits are given on the cross section ofγγ→K+\(\overline {K^0 } \)π− orK−K0π+ between 1.4 and 3.2 GeV and on the product of the γγ width times the branching ratio into theK\(\bar K\)π final states for theηc(2980) and the ι(1440), yieldingΓ(γγ)→i(1440))·BR(i(1440)→K\(\bar K\)π<2.2 keV at 95% C.L.

2 data tables

Data read from graph.. Corrected for the angular distribution, which is assumed to be sin(theta)**4 for W > 1.14 GeV and isotropic in the first bin.

Data read from graph.


EVIDENCE FOR IOTA PRODUCTION IN HIGH-ENERGY e+ e- ANNIHILATION

The JADE collaboration Bartel, W. ; Becker, L. ; Cords, D. ; et al.
DESY-85-081, 1985.
Inspire Record 220907 DOI 10.17182/hepdata.45208

None

1 data table

Background subtracted.


Inclusive Strange Particle Production in Single Vee Events in 200-GeV/c $\pi^-$ N Interactions

Mikocki, S. ; Ficenec, J.R. ; Torres, S. ; et al.
Phys.Rev.D 34 (1986) 42, 1986.
Inspire Record 218617 DOI 10.17182/hepdata.23427

For the reaction π−N→V0X, where V0 is a Ks0, Λ, and Λ¯ and X are charged particles, we measured the transverse- and longitudinal-momentum distributions, and inclusive cross sections for the V0 and for K*±(892), Σ±(1385), and Ξ±(1321). We compare our results with predictions of quark-counting rules, and conclude that valence quarks play an important role in strange-particle production.

1 data table

No description provided.


Observation of Double Phi Meson Production in 400 GeV/c Proton - Nucleon Interactions

Davenport, T.F. ; Albright, John R. ; Goldman, J.H. ; et al.
Phys.Rev.D 33 (1986) 2519, 1986.
Inspire Record 218616 DOI 10.17182/hepdata.23536

The production of φ-meson pairs has been observed in 400-GeV/c proton-nucleon interactions at the Fermilab multiparticle spectrometer in the inclusive reaction pN→φφ+X, where each φ decays to a K+K− pair. A fast (200 nsec) high-level processor was used to selectively trigger on events containing two pairs of oppositely charged kaons having low invariant masses. The experimental apparatus and trigger processor are described. The cross section for φφ production and an upper limit for ηc production are presented.

1 data table

No description provided.


Study of the Reaction $p p$ (Polarized) $\to p \pi^+ n$ With Polarized Beam From 3-{GeV}/$c$ to 12-{GeV}/$c$

Wicklund, A.B. ; Arenton, M.W. ; Ayres, D.S. ; et al.
Phys.Rev.D 34 (1986) 19, 1986.
Inspire Record 17565 DOI 10.17182/hepdata.3936

We present density-matrix elements and single-spin correlations for the reaction p↑p→pπ+n at 3, 4, 6, and 11.75 GeV/c, using both longitudinal and transverse beam polarizations. For small momentum transfers, the spin correlations are mainly due to off-shell π+p elastic scattering, while for larger t there are large polarization effects associated with the production dynamics for p↑p→Δ++n. Comparison of longitudinal and transverse polarization correlations suggests that the Δ++-production spin effects are due mainly to unnatural-parity exchanges. We present a model-dependent amplitude analysis, and extract the energy dependence of the natural- and unnatural-parity-exchange contributions.

36 data tables

Unpolarized cross sections.

Unpolarized cross sections.

Unpolarized cross sections.

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Tests of the Standard Model in Leptonic Reactions at {PETRA} Energies

The JADE collaboration Bartel, W. ; Becker, L. ; Cords, D. ; et al.
Z.Phys.C 30 (1986) 371, 1986.
Inspire Record 222566 DOI 10.17182/hepdata.48419

An analysis of the three leptonic reactionse+e−→e+e−,μ+μ− andτ+τ− over a wide range of energy,\(12< \sqrt s< 46.78 GeV\) is presented. The data were obtained with the JADE detector at thee+e− storage ring PETRA. They are compared to predictions of electroweak theories, in particular the standard model. For the total cross-sections of all three reactions and for the differential cross-section of Bhabha scattering no deviation from QED is found over the entire energy range. The differential cross-sections of μ and τ pairs at high energies show the angular asymmetry predicted by electroweak interference. The axial-vector and vector weak coupling constant, sin2θW andMZ are determined and compared to other measurements. Finally, limits on deviations from the standard model are given.

36 data tables

No description provided.

No description provided.

No description provided.

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