Date

Search for Top Quark in e+ e- Collisions at s**(1/2) = 52-GeV

The TOPAZ collaboration Adachi, I. ; Aihara, H. ; Dijkstra, H.B. ; et al.
Phys.Rev.Lett. 60 (1988) 97, 1988.
Inspire Record 251830 DOI 10.17182/hepdata.20141

We searched for possible signatures of top-quark production in 508 e+e− hadronic annihilation events collected at s=52 GeV by the TOPAZ detector at the KEK e+e− collider TRISTAN. The observed hadronic cross section and shape of hadronic events are consistent with the standard-model predictions without top quarks. A lower limit (95% confidence level) on the mass of the lightest top meson is set at 25.8 GeV.

1 data table

No description provided.


Production of $\eta$ Mesons in $e^+ e^-$ Annihilations at $\sqrt{s}=29$-{GeV}

The HRS collaboration Abachi, S. ; Akerlof, C. ; Baringer, P. ; et al.
Phys.Lett.B 205 (1988) 111-114, 1988.
Inspire Record 250824 DOI 10.17182/hepdata.29979

Data from e + e − annihilations at 29 GeV have been used to measure the production cross section and fragmentation function of η mesons. The signal is observed in the η → γγ decay channel. The fragmentation for p η >1.5 GeV/ c agrees well with the prediction of the Lund model, whereas the prediction of the Webber model lies above the data. The mean multiplicity is measured to be 〈 n η 〉=0.58±0.10 η mesons per hadronic event, of which 0.51 represents the direct production of η and η ′ mesons in the fragmentation chain.

2 data tables

Statistical errors only.

Extrapolated to full z range using LUND model.


Measurement of the Spin Density Matrix of $D^*$ Mesons Produced in $e^+ e^-$ Annihilations

The HRS collaboration Abachi, S. ; Akerlof, C. ; Baringer, P. ; et al.
Phys.Lett.B 199 (1987) 585-590, 1987.
Inspire Record 250823 DOI 10.17182/hepdata.30012

Vector mesons produced in the reaction e + e − →V+X at √ s =29 GeV were isolated by observing D ∗ mesons through the D ∗+ → D 0 π + decay. The D 0 decay modes used are D 0 →K3 π , K π , K π , and K π ( π 0 ). The data, which correspond to an integrated luminosity of 300 pb −1 , were collected by the High Resolution Spectrometer at PEP. Spin density matrix elements for the D ∗ meson are measured as a function of the energy sharing variable Z D ∗ . There is no evidence for alignment of D ∗ mesons produced in e + e − annihilation at our energy.

6 data tables

Spin density matrix for D0 --> K PI decay mode.

Spin density matrix for D0 --> K 3PI decay mode.

Spin density matrix for D0 --> K PI (PI0) decay mode.

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Hyperon Production in $e^+ e^-$ Annihilation at 10-{GeV} Center-of-mass Energy

The ARGUS collaboration Albrecht, H. ; Binder, U. ; Bockmann, P. ; et al.
Z.Phys.C 39 (1988) 177, 1988.
Inspire Record 251097 DOI 10.17182/hepdata.1697

The production cross sections for the Λ, Σ0, Ξ−, Σ0 (1385), Ξ0 (1530) and Ω− hyperons have been measured, both in the continuum and in direct ϒ decays. Baryon rates in direct ϒ decays are enhanced by a factor of 2.5 or more compared to the continuum. Such a large baryon enhancement cannot be explained by standard fragmentation models. The strangeness suppression for baryons and mesons turns out to be the same. A strong suppression of spin 3/2 states is observed.

23 data tables

Hyperon rates per multihadronic event in direct UPSILON decays.

Hyperon rates per multihadronic event in the continuum.

LAMBDA spectrum (1/SIG(had))*D(SIG)/D(X) for UPSILON (1S) direct decays, with X = P/Pmax.

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Azimuthal Energy Flow in Deep Inelastic Neutrino Scattering

Mukherjee, A. ; Bofill, J. ; Busza, W. ; et al.
Phys.Rev.Lett. 60 (1988) 991, 1988.
Inspire Record 252080 DOI 10.17182/hepdata.3134

The azimuthal dependence of the flow of hadronic energy about the momentum-transfer direction in charged-current deep-inelastic neutrino-nucleon scattering is used to study gluon emission and the transverse momentum 〈kT〉 of partons confined inside the nucleon. A 7-standard-deviation azimuthal asymmetry is observed indicating an average 〈kT〉=0.303±0.041 GeV/c.

4 data tables

No description provided.

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Search for New Heavy Quarks at the CERN Proton - anti-Proton Collider

The UA1 collaboration Albajar, C. ; Albrow, M.G. ; Allkofer, O.C. ; et al.
Z.Phys.C 37 (1988) 505-525, 1988.
Inspire Record 250763 DOI 10.17182/hepdata.15651

A search has also been made for a fourth generation, charge 1/3 quark (b'). Assuming that theb' mass is smaller than that of the top quark and that it can-not be produced inW decays, the mass limits, using the above procedures, are respectivelymb'>32 GeV/c2 andmb'>44 GeV/c2, both at 95% confidence level.

0 data tables

Charged $K^*$ Production in $e^+ e^-$ Annihilations at 29-{GeV}

Abachi, S. ; Baringer, Philip S. ; Bylsma, B.G. ; et al.
Phys.Lett.B 199 (1987) 151-154, 1987.
Inspire Record 22433 DOI 10.17182/hepdata.6521

We report a measurement of the charged K ∗ (892) production in e + e − annihilations at 29 GeV center-of-mass energy. The 300 pb −1 data sample used for this analysis is obtained with the High Resolution Spectrometer at the SLAC storage ring PEP. The total mean multiplicity is measured to be 〈n K ∗± (892) 〉=0.62±0.045±0.04 per hadronic event. Evidence is also given for the production of a charged K 2 ∗ (1430) tensor meson.

6 data tables

Extrapolation to full x-range using Lund model.

Data requested from authors.

Extrapolation to full x-range usisng fragmentation friction predicted by the Webber cluster model.

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The Transverse Energy Distribution in $^{16}$O - Nucleus Collisions at 60-{GeV} and 200-{GeV} Per Nucleon

The HELIOS collaboration Akesson, T. ; Almehed, S. ; Angelis, A.L.S. ; et al.
Z.Phys.C 38 (1988) 383, 1988.
Inspire Record 250767 DOI 10.17182/hepdata.15648

None

6 data tables

No description provided.

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The Transverse Energy Distribution in Hadron - Lead Collisions

Åkesson, T. ; Choi, Y. ; Dam, P. ; et al.
Z.Phys.C 38 (1988) 397, 1988.
Inspire Record 250759 DOI 10.17182/hepdata.15655

The transverse energy cross-sectiondσ/dET has been measured in the pseudorapidity region 0.6<η<2.4 for hadron-lead collisions at 200 GeV/c incident hadron momentum. TheET distribution extends to 40 GeV, which is twice the kinematic limit forp-p collisions at the same incident beam momentum. The distribution ofET is found to shift towards low pseudorapidities with increasing total transverse energy.

1 data table

Statistical error only.


Energy Dependence of the Charge Asymmetry a ($T (\pi$), $\theta$) in $\pi d$ Elastic Scattering

Smith, G.R. ; Gill, D.R. ; Ottewell, D. ; et al.
Phys.Rev.C 38 (1988) 240-250, 1988.
Inspire Record 250814 DOI 10.17182/hepdata.26223

Angular distributions of charge asymmetry A(Tπ,θ), have been measured for πd elastic scattering. Data were obtained in the backward hemisphere for pion bombarding energies of 143, 180, 220, and 256 MeV. The results are compared with predictions employing different mass and width parameters for the delta isobars.

4 data tables

No description provided.

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