Date

Study of Hadronic Decays of the $\Z^0$ Boson

The DELPHI collaboration Aarnio, P. ; Abreu, P. ; Adam, W. ; et al.
Phys.Lett.B 240 (1990) 271-282, 1990.
Inspire Record 294894 DOI 10.17182/hepdata.49562

Hadronic decays of Z 0 bosons are studied in the Delphi detector. Global event variables and singel particles inclusive distributions are compared with QCD-based predictions. The mean charged multiplicity is found to be 20.6±1.0 (stat+syst). The mean values of the sphericity, aplanarity, thrust, minor value, p in T and p out T are compared with values found at lower energy e + e − colliders.

13 data tables

Corrected Sphericity distribution. Statistical errors only.

Corrected Aplanarity distribution. Statistical errors only.

Corrected Q3-Q2 distribution. Statistical errors only.

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Measurements of Charged Particle Inclusive Distributions in Hadronic Decays of the $Z$ Boson

Abrams, G.S. ; Adolphsen, Chris ; Averill, D. ; et al.
Phys.Rev.Lett. 64 (1990) 1334, 1990.
Inspire Record 283799 DOI 10.17182/hepdata.19999

We have measured inclusive distributions for charged particles in hadronic decays of the Z boson. The variables chosen for study were charged-particle multiplicity, scaled momentum, and momenta transverse to the sphericity axes. The distributions have been corrected for detector effects and are compared with data from e+e− annihilation at lower energies and with the predictions of several QCD-based models. The data are in reasonable agreement with expectations.

4 data tables

Mean corrected charged particle multiplicity.

Corrected charged particle X distributions. Errors are statistical and systematic combined.

Corrected charged particle PTIN distributions. Errors are statistical and systematic combined.

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A Search for the Top and $b^\prime$ Quarks in Hadronic $\Z^0$ Decays

The OPAL collaboration Akrawy, M.Z. ; Alexander, G. ; Allison, J. ; et al.
Phys.Lett.B 236 (1990) 364-374, 1990.
Inspire Record 283784 DOI 10.17182/hepdata.29702

We report on a search for new quarks in hadronic Z° decays. From the event shape analysis of a data sample containing 2185 multihadronic annihilation events, we observe no evidence for the top or b' quarks. We derive limits for the top and b' quark masses under the assumption of various possible standard model and non-standard model decay schemes. Our search is sensitive to quark masses larger than 23 GeV/ c 2 ; it yields the following lower limits at a 95% confidence level: 44.5 GeV/ c 2 for the top quark mass and 45.2 GeV/ c 2 for the b′ quark mass.

1 data table

Measured event shape distributions - uncorrected.


MULTI - HADRON EVENT PROPERTIES IN e+ e- ANNIHILATION AT s**(1/2) = 52-GeV to 57-GeV

The AMY collaboration Li, Y.K. ; Li, J. ; Cheng, C.P. ; et al.
Phys.Rev.D 41 (1990) 2675, 1990.
Inspire Record 283337 DOI 10.17182/hepdata.38416

We present the general properties of multihadron final states produced by e+e− annihilation at center-of-mass energies from 52 to 57 GeV in the AMY detector at the KEK collider TRISTAN. Global shape, inclusive charged-particle, and particle-flow distributions are presented. Our measurements are compared with QCD+fragmentation models that use either leading-logarithmic parton-shower evolution or QCD matrix elements at the parton level, and either string or cluster fragmentation for hadronization.

22 data tables

Rapidity distribution with respect to the Thrust axis.

Charged particle X distribution.

Charged particle PL distribution.

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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 is found to be approximately constant up to the highest accessible values ofE⊥.

3 data tables

No description provided.

No description provided.

No description provided.


High $p_T \gamma$ and $\pi^0$ Production, Inclusive and With a Recoil Hadronic Jet, in $p p$ Collisions at $\sqrt{s}=63$-{GeV}

The Axial Field Spectrometer collaboration Akesson, T. ; Albrow, M.G. ; Almehed, S. ; et al.
Sov.J.Nucl.Phys. 51 (1990) 836-845, 1990.
Inspire Record 281284 DOI 10.17182/hepdata.48816

None

3 data tables

Errors are combined statistical and systematic.

Errors are combined statistical and systematic.

Errors are combined statistical and systematic.


Hyperon Production at 200-{GeV} and 900-{GeV} Center-of-mass Energy

The UA5 collaboration Ansorge, R.E. ; Asman, B. ; Burow, L. ; et al.
Nucl.Phys.B 328 (1989) 36-58, 1989.
Inspire Record 277298 DOI 10.17182/hepdata.33174

The production of Λ 's and Ξ − 's in proton-antiproton collisions at 200 and 900 GeV c.m. energy has been studied using decays observed in the UA5 streamer chambers. The results are compared to previously published 546 GeV data, to results from other experiments, and to four theoretical models. The Λ yield per inelastic event is estimated to be 0.42±0.11 at 200 GeV and 0.66±0.14 at 900 GeV. We find a mean number of Ξ − 's per inelastic collision of 0.03 −0.02 +0.04 at 200 GeV and 0.06 −0.03 +0.05 at 900 GeV. The average transverse momentum of Λ's in the rapidity region | y |⩽2 is found to be 0.80 −0.14 +0.20 GeV/ c at 200 GeV and 0.74±0.09 GeV/ c at 900 GeV. The average transverse momentum of Ξ − 's in the rapidity region | y |⩽3 is estimated to be 0.8 −0.2 +0.4 GeV/ c at 200 GeV and 0.7 −0.1 +0.2 GeV/ c at 900 GeV which is lower than the unexpectedly high value of 1.1±0.2 GeV/ c measured at 546 GeV. The ratio of Ξ − production to Λ production in the region | y |⩽2, p t >1 GeV/ c is 0.07 −0.04 +0.08 at 900 GeV. This value is consistent with the ratio found in e + e − collisions and lower energy pp collisions but lower than the value obtained at 546 GeV. The average particle composition of events at 200 and 900 GeV, estimated using UA5 data, is presented.

9 data tables

Corrected lambda transverse momentum distributions. Numerical values supplied by F. Lotse. Data at 546 GeV are taken from an earlier publication - Phys. Rep. 154 (87) 247.

Data at 546 GeV are taken from an earlier publication - Phys. Rep. 154 (87) 247.

Corrected lambda transverse momentum distributions. Numerical values supplied by F. Lotse. Data at 546 GeV are taken from an earlier publication - Phys. Rep. 154 (87) 247.

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Inclusive Photoproduction of Single Charged Particles at High $p_T$

The OMEGA Photon collaboration Apsimon, R.J. ; Atkinson, M. ; Baake, M. ; et al.
Z.Phys.C 43 (1989) 63, 1989.
Inspire Record 276890 DOI 10.17182/hepdata.15435

Single charged-particle inclusive cross sections for photon, pion and kaon beams on hydrogen at the CERN-SPS are presented as functions ofpT andxF. Data cover the range 0.01.6 GeV/c for the photon-induced data. Using the hadron-induced data to estimate the hadronic behaviour of the photon, the difference distributions and ratios of cross sections are a measure of the contribution of the point-like photon interactions. The data are compared with QCD calculations and show broadly similar features.

4 data tables

No description provided.

No description provided.

No description provided.

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A Study of $K^0_S$, $\Lambda$ and $\bar{\Lambda}$ Production in 60-{GeV} and 200-{GeV} Per Nucleon O Au and $p$ Au Collisions With a Streamer Chamber Detector at the {CERN} {SPS}

The NA35 collaboration Bamberger, A. ; Bartke, J. ; Bialkowska, H. ; et al.
Z.Phys.C 43 (1989) 25, 1989.
Inspire Record 276686 DOI 10.17182/hepdata.15456

The production of neutral strange particlesKso, Λ and\(\bar \Lambda \) has been studied in 60 and 200 GeV per nucleon OAu and pAu collisions with the streamer chamber vertex spectrometer of the NA35 experiment at the CERN-SPS accelerator. Ratios of neutral strange particle production to negatively charged particle production in selected regions of phase space were measured to be the same in OAu and pAu reactions. The rates of strange particle production in central OAu collisions are about a factor of 16 higher than in pAu collisions when compared in the same regions of phase space. If an enhancement of strange particle production in OAu collisions relative to pAu collisions is considered to be a signature for quark-gluon plasma formation, no evidence supporting it is observed. The experimental results are compared to the Lund FRITIOF model.

22 data tables

No description provided.

No description provided.

No description provided.

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Lambda0 and anti-Lambda0 Production from Proton - anti-Proton Collisions at s**(1/2) = 1.8-TeV

The E735 collaboration Banerjee, S. ; Beery, P.D. ; Biswas, N.N. ; et al.
Phys.Rev.Lett. 62 (1989) 12, 1989.
Inspire Record 24875 DOI 10.17182/hepdata.20125

The transverse-momentum spectra of lambdas (Λ0, Λ¯0) produced in the central region has been measured in p¯p collisions at s=1.8 TeV at the Fermilab Collider. We find that the average transverse momentum of the lambdas increases more rapidly with center-of-mass energy than that of charged particles, and the ratio of lambdas to charged particles increases as a function of center-of-mass energy.

4 data tables

No description provided.

No description provided.

No description provided.

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