Barish, S.J.
E+ E- Scattering
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Electroweak Effects in $e^+ e^- \to \mu^+ \mu^-$ at 29-{GeV}

Fernandez, E. ; Ford, William T. ; Read, Alexander L. ; et al.
Phys.Rev.Lett. 50 (1983) 1238, 1983.
Inspire Record 188749 DOI 10.17182/hepdata.20560

A measurement of the cross section for production of collinear muon pairs based upon a sample of about 3000 events observed in the MAC detector at the storage ring PEP is presented. From the angular asymmetry Aμμ=0.076±0.018 the axial-vector weak neutral coupling is found to be given by gAegAμ=0.31±0.08.

2 data tables
Table 1

Data on non-collinearity and angular distribution.

Table 2

Asymmetry measurement based on extrapolation of number of events to 4 PI acceptance.


Fragmentation of Heavy Quarks Produced in $e^+ e^-$ Annihilation

Fernandez, E. ; Ford, William T. ; Read, Alexander L. ; et al.
Phys.Rev.Lett. 50 (1983) 2054, 1983.
Inspire Record 189417 DOI 10.17182/hepdata.20548

Identification of muons in hadronic events from e+e− annihilation observed in the MAC detector at the storage ring PEP provides flavor tagging of heavy primary quarks. A sample enriched in events from bb¯ production is obtained and the b-quark fragmentation function is inferred from the momentum spectrum of the muons. The b quark is found to fragment predominantly with high values of z, with 〈zb〉=0.8±0.1, and to have an over-all semimuonic branching fraction of (15.5−2.9+5.4)%.

2 data tables
Table 1

No description provided.

Table 2

No description provided.


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.


WEAK NEUTRAL CURRENT EFFECTS IN e+ e- ---> mu+ mu- AT 29-GeV

Fernandez, E. ; Ford, William T. ; Read, Alexander L. ; et al.
SLAC-PUB-3133, 1983.
Inspire Record 190846 DOI 10.17182/hepdata.18659

None

2 data tables
Table 1

No description provided.

Table 2

Data extrapolated to full solid angle.


Search for Singly Produced Supersymmetric Electrons in $e^+ e^-$ Interactions

Fernandez, E. ; Ford, William T. ; Read, Alexander L. ; et al.
Phys.Rev.Lett. 52 (1984) 22, 1984.
Inspire Record 192872 DOI 10.17182/hepdata.20447

A search for supersymmetric electron production via the reaction e+e−→e±γ̃ẽ∓ followed by the decay ẽ∓→e∓γ̃ has been performed with the MAC detector at the electron-positron storage ring PEP. No candidates were found in a sample corresponding to an integrated luminosity of 36.4 pb−1. For a massless γ̃ this corresponds to a lower limit on the ẽ mass of 22.4 GeV/c2 at the 95% confidence level.

2 data tables
Table 1

No description provided.

Table 2

No description provided.


Exclusive Production of Hadron Pairs at Large Momentum Transfer in Photon-photon Interactions

The PLUTO collaboration Berger, Christoph ; Deuter, A. ; Genzel, H. ; et al.
Phys.Lett.B 137 (1984) 267-271, 1984.
Inspire Record 194772 DOI 10.17182/hepdata.30576

We report on the exclusive production of π, K and proton pairs from photon-photon interactions at momentum transfers | t |⩾1 GeV 2 . Using the PLUTO detector at the e + e − storage ring PETRA, we have observed 15 events in an integrated luminosity of 41.7 pb −1 . The data lie far below the expectations for point-like hadrons, and are in reasonable agreement with the QCD-based predictions of Brodsky and Lepage.

3 data tables
Table 1

THIS METHOD OF ANALYSIS OF THE OBSERVED RATIO OF HADRON TO MUON PAIRS, IS TIED TO THE SPECIFIC DETECTOR ACCEPTANCE, BUT HAS THE ADVANTAGE OF BEING VIRTUALLY INDEPENDENT OF THE HADRON MASSES.

Table 2

SEE COMMENT IN PREVIOUS TABLE.

Table 3

THIS METHOD OF ANALYSIS OF THE CROSS SECTION AT 90 DEG IN THE CM AS A FUNCTION OF PCM IS MORE EASILY COMPARED WITH THEORETICAL PREDICTIONS BUT MORE DEPENDENT ON THE SPECIFIC HADRON MASSES.


Charged $D^*$ Production in $e^+ e^-$ Annihilation at 29-{GeV} and a Limit on D0 - Anti-d0 Mixing

Yamamoto, H. ; Atwood, W.B. ; Baillon, P. ; et al.
Phys.Rev.Lett. 54 (1985) 522-525, 1985.
Inspire Record 205132 DOI 10.17182/hepdata.20325

We have studied inclusive D*± production using the DELCO detector at PEP. Our technique involved kaon identification in the momentum range above 3.2 GeV/c using a threshold gas Čerenkov counter. This leads to a model-independent upper limit on D0−D¯0 mixing of 8.1% (90% confidence level). We also have measured the charm fragmentation function, which peaks at x≡PD*(Ebeam2−MD*2)12 of 0.56±0.06(stat.), and the total cross section for D* production, σ(D*±)=0.140±0.021(stat.)±0.032(syst.) nb (x>0.3, with radiative correction).

2 data tables
Table 1

No description provided.

Table 2

SYSTEMATIC ERROR DOES NOT INCLUDE THE UNCERTAINTY ON THE BRANCHING RATIOS USED.


rivet Analysis
Precision Measurement of the Total Cross-section for $e^+ e^- \to$ Hadrons at a Center-of-mass Energy of 29-{GeV}

Fernandez, E. ; Ford, William T. ; Qi, N. ; et al.
Phys.Rev.D 31 (1985) 1537, 1985.
Inspire Record 206052 DOI 10.17182/hepdata.4048

We report a high-precision measurement of the ratio R of the total cross section for e+e−→hadrons to that for e+e−→μ+μ−, at a center-of-mass energy of 29.0 GeV using the MAC detector. The result is R=3.96±0.09. This value of R is used to determine a value of the strong coupling constant αs of 0.23±0.06, nearly independent of fragmentation models. Two different analysis methods having quite different event-selection criteria have been used and the results are in agreement. Particular attention has been given to the study of systematic errors. New higher-order QED calculations are used for the luminosity determination and the acceptance for hadrons.

2 data tables
Table 1

No description provided.

Table 2

No description provided.


Tests of the Standard Model With Lepton Pair Production in $e^+ e^-$ Reactions

The PLUTO collaboration Berger, Christoph ; Deuter, A. ; Genzel, H. ; et al.
Z.Phys.C 27 (1985) 341, 1985.
Inspire Record 207950 DOI 10.17182/hepdata.1917

The differential cross section of the reactione+e−→e+e− at a c.m. energy of 34.7 GeV has been measured. The result, together with our previously measurede+e−→α+α− data, are compared with the standard model predictions. We obtain for the weak neutral current couplings the valuesgv2=0.09×0.06,ga2=0.38×0.08. A fit of the Weinberg mixing angle gives the valuegv2=0.09×0.06,ga2=0.038×0.08. The data are also used to set limits on possible deviations from the pointlike structure of leptons. An upper limit for thee+e− coupling to a heavy spin 0 boson is also given.

3 data tables
Table 1

Fully corrected results for Bhabha scattering.

Table 2

The differential cross section for Bhabha scattering.

Table 3

??? CONSTANTS ???.


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.