Dainton, J.B
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$\tau$ Production and Decay With the Cello Detector at {PETRA}

The CELLO collaboration Behrend, H.J. ; Criegee, L. ; Dainton, J.B. ; et al.
Phys.Lett.B 222 (1989) 163-172, 1989.
Inspire Record 276859 DOI 10.17182/hepdata.29824

The reaction e + e − → τ + τ − has been studied at centre of mass energies between 14.0 and 46.8 GeV with the CELLO detector at the PETRA e + e − collider. We present results for the cross section σ τ and the charge asymmetry A τ . The results are in good agreement with the standard model. We have also measured the topological decay rates BR 1 , BR 3 and BR 5 for the inclusive decay of the τ lepton into one, three and five charge particles. The results confirm and improve earlier CELLO measurements at other energies. We find for the combined values at all energies BR 1 = (84.9 ± 0.4 ± 0.3)%, BR 3 = (15.0 ± 0.4 ± 0.3)% and BR 5 = (0.16 ± 0.13 ± 0.04)%.

3 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

Corrected for radiative effects and background contributions.


Measurement of the Reaction $\gamma \gamma \to \rho^+ \rho^-$ With the Cello Detector

The CELLO collaboration Behrend, H.J. ; Criegee, L. ; Dainton, J.B. ; et al.
Phys.Lett.B 218 (1989) 493-498, 1989.
Inspire Record 267081 DOI 10.17182/hepdata.29842

Results on the reaction γγ → π + π − π 0 π 0 are presented. There is clear evidence for correlated ϱ + ϱ − production. The cross section is much lower than for γγ → ϱ 0 ϱ 0 .

2 data tables
Table 1

Results using 3 parameter fit (rho+ rho-, rho+- pi+- pi0, and non-resonant 4pi) to data.

Table 2

Results using 2 parameter fit (rho+ rho-, and non-resonant 4pi) to data.


Measurement of the Total Photon-photon Cross-section for the Production of Hadrons at Small $Q^2$

The PLUTO collaboration Berger, Christoph ; Deuter, A. ; Genzel, H. ; et al.
Phys.Lett.B 149 (1984) 421-426, 1984.
Inspire Record 204850 DOI 10.17182/hepdata.30489

The total photon-photon cross section for the production of hadrons, σ γγ ( W , Q 2 ), has been measured in the single-tag condition for 0.1 < Q 2 < 1.0 GeV 2 and 1.5 < W < GeV. The results are based on 2929 multihadron events obtained with the PLUTO detector at PETRA. The Q 2 dependence of σ γγ average over W can be described by GVDM. The dependence of σ γγ on the mass W of the hadronic final state has been extracted at Q 2 = 0.44 GeV 2 by unfolding the effects of experimental resolution and acceptance. The cross section is found to rise at small W . The result is compared with VDM and the parton model.

2 data tables
Table 1

No description provided.

Table 2

DATA EXTRAPOLATED TO Q**2=0 USING THE GENERALIZED VECTOR MESON DOMINANCE MODEL (GVDM).


rivet Analysis
Search for New Heavy Quarks in $e^+ e^-$ Collisions Up to 46.78-{GeV} Center-of-mass Energy

The CELLO collaboration Behrend, H.J. ; Burger, J. ; Criegee, L. ; et al.
Phys.Lett.B 144 (1984) 297-301, 1984.
Inspire Record 202783 DOI 10.17182/hepdata.30514

The total e + e − annihilation onto hadron has been measured at CM energies between 33.00 and 36.72 GeV and between 38.66 and 46.78 GeV in steps of 20 and 30 MeV respectively. The average of the ratio R = σ ( e + e − → hadrons )/ σ is 〈 R 〉=3.85±0.12 and 〈 R 〉=4.04±0.10 for the two energy ranges. The systematic error on 〈 R 〉 is 0.31. Both values are consistent with the expectation for the known coloured quarks u, d, s, c and b. No evidence was found for the production of new quarks. If the largest fluctuation in R is interpreted as a narrow resonance, it corresponds to a product of the electronic width and the hadronic branching ratio Γ ee B had >2.9 keV at the 95% confidence level, well below the value expected for the toponium vector ground state with charge 2 3 e . The observed number of aplanar final states rules out the continuum production of a a new heavy flavour with pointlike cross section up to a CM energy of 45.4 GeV for a quarck charge of 1 3 e . and up to 46.6 GeV for 2 3 e at the 95% confidence level.

2 data tables
Table 1

ENERGY SCANS IN 20(30) MEV STEPS.

Table 2

No description provided.


Measurements of Tau Lepton Production and Decay

The PLUTO collaboration Berger, Christoph ; Genzel, H. ; Lackas, W. ; et al.
Z.Phys.C 28 (1985) 1, 1985.
Inspire Record 213241 DOI 10.17182/hepdata.16019

We have studied 419 τ pair events produced in the reactione+e−→τ+ τ− at a c.m. energy of 34.6 GeV. We measure the cross section and angular distribution, as well as the decay branching ratios. The production characteristics are consistent with the Standard Electroweak Model predictions of γ andZ0 interference. The branching ratios are generally consistent with the τ decaying according to standard weak interaction principles, but we observe somewhat more decays resulting in single charged hadrons plus neutrals than are predicted by present theory.

3 data tables
Table 1

Corrected for radiative effects.

Table 2

Measured cross section relative to Standard Model Prediction.

Table 3

Asymmetry based on fits to angular distribution.


rivet Analysis
Measurement of Transverse Momenta in $e^+ e^-$ Annihilation Jets at {PETRA}

The PLUTO collaboration Berger, Christoph ; Genzel, H. ; Lackas, W. ; et al.
Z.Phys.C 22 (1984) 103, 1984.
Inspire Record 191161 DOI 10.17182/hepdata.16268

Transverse particle momenta have been measured ine+e− annihilation into hadrons at c.m. energies between 9.4 and 31.6 GeV. The data are fully corrected for detector effects and radiation in the initial state. A comparison is made with recent QCD calculations.

3 data tables
Table 1

MEASUREMENTS MADE WITH RESPECT TO THE SPHERICITY AXIS.

Table 2

MEASUREMENTS MADE WITH RESPECT TO THE THRUST AXIS.

Table 3

MEASUREMENTS MADE WITH RESPECT TO THE MOST ENERGETIC PARTON AXIS.


rivet Analysis
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
Table 1

Corrected energy-energy correlation data.

Table 2

CORRECTED FORWARD-BACKWARD ASYMMETRY.


A Measurement of the $Q^2$ and $W$ Dependence of the $\gamma \gamma$ Total Cross-section for Hadron Production

The PLUTO collaboration Berger, Christoph ; Deuter, A. ; Genzel, H. ; et al.
Z.Phys.C 26 (1984) 353, 1984.
Inspire Record 204849 DOI 10.17182/hepdata.16195

A measurement of the γγ total cross section, σγγ(Q2W), is presented for theQ2 range 0.1 to 100 GeV2, and for the massW of the hadronic final state between 1.5 and 10 GeV. The dependence of σγγ on bothQ2 andW is measured. The results are compared with theoretical predictions. It is found that the data are well described by a sum of quarkparton model and vector dominance contributions.

4 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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Measurement of event shape variables in deep inelastic e p scattering.

The H1 collaboration Adloff, C. ; Aid, S. ; Anderson, M. ; et al.
Phys.Lett.B 406 (1997) 256-270, 1997.
Inspire Record 443753 DOI 10.17182/hepdata.23948

Deep inelastic e^+ scattering data, taken with the H1 detector at HERA, are used to study the event shape variables thrust, jet broadening and jet mass in the current hemisphere of the Breit frame over a large range of momentum transfers Q between 7 GeV and 100 GeV. The data are compared with results from e^+e^- experiments. Using second order QCD calculations and an approach to relate hadronisation effects to power corrections an analysis of the Q dependences of the means of the event shape parameters is presented, from which both the power corrections and the strong coupling constant are determined without any assumption on fragmentation models. The power corrections of all event shape variables investigated follow a 1/Q behaviour and can be described by a common parameter alpha_0.

6 data tables
Table 1

The data on the differential event shape distrubutions are shown only as a illustration to show the agreement with the Lepto and pQCD calculations and contain only statistical errors. The authors are preparing another paper which details these differential distributions including full point-to-point systematics.

Table 2

Usual definition of Thrust.

Table 3

The same as usual thrust definition but with the thrust axis replaced by the current hemisphere axis (0,0,-1), where positive Z direction coincide with theincoming proton beam direction.

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Total photoproduction cross-section measurement at HERA energies

The H1 collaboration Ahmed, T. ; Andreev, V. ; Andrieu, B. ; et al.
Phys.Lett.B 299 (1993) 374-384, 1993.
Inspire Record 340891 DOI 10.17182/hepdata.45139

We present first results on the total photoproduction cross section measurement with the H1 detector at HERA. The data were extracted from low Q 2 collisions of 26.7 GeV electrons with 820 GeV protons. The γp total cross section has been measured by two independent methods in the γp center of mass energy range from 90 to 290 GeV. For an average center of mass energy of 195 GeV a value of σ tot ( γp ) = 159 ± 7 (stat.) ± 20 (syst.) μb was obtained.

2 data tables
Table 1

Data from tagged sample.

Table 2

Data from untagged sample.