Marini, A.
E+ E- Scattering
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Electroweak Effects in $e^+ e^- \to \tau^+ \tau^-$ at 29-{GeV}

Fernandez, E. ; Ford, William T. ; Qi, N. ; et al.
Phys.Rev.Lett. 54 (1985) 1620, 1985.
Inspire Record 207555 DOI 10.17182/hepdata.3267

A high-statistics measurement is presented of the cross section for the process e+e−→τ+τ− at s=29 GeV from the MAC detector at PEP. A fit to the angular distribution of our sample of 10 153 events with |cosθ|<0.9 gives an asymmetry Aττ=−0.055±0.012±0.005 from which we find the product of electron and tau axial-vector weak neutral couplings gAegAτ=0.22±0.05.

3 data tables match query
Table 2

Data extrapolated to full acceptance.

Table 3

No description provided.

Table 4

No description provided.


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 match query
Table 1

No description provided.

Table 2

No description provided.


MEASUREMENTS OF THE EM TIMELIKE FORM-FACTORS FOR KAON AND PION AT S**(1/2) = 1.5-GEV

Esposito, B. ; Marini, A. ; Piano Mortari, Giovanni ; et al.
Lett.Nuovo Cim. 28 (1980) 337-342, 1980.
Inspire Record 158283 DOI 10.17182/hepdata.37369

None

1 data table match query
Table 1

No description provided.


Hadronic Cross-section in $e^+ e^-$ Annihilation From 1.45-{GeV} to 1.80-{GeV}

Esposito, B. ; Marini, A. ; Piano Mortari, Giovanni ; et al.
Lett.Nuovo Cim. 30 (1981) 65-71, 1981.
Inspire Record 170172 DOI 10.17182/hepdata.37368

None

2 data tables match query
Table 1

CROSS SECTION EXCLUDES ANY CONTRIBUTION FROM TWO-BODY FINAL STATES (PI+ PI- AND K+ K-).

Table 2

CHARGED AND NEUTRAL MULTIPLICITIES.


STUDY OF (PI+ PI- PI+ PI-) AND (PI+ PI- PI0) CHANNEL IN E+ E- ANNIHILATION AT 1.450-GEV - 1.875-GEV center-of-mass ENERGY

Esposito, B. ; Marini, A. ; Ronga, F. ; et al.
Lett.Nuovo Cim. 28 (1980) 195-200, 1980.
Inspire Record 158282 DOI 10.17182/hepdata.37366

None

2 data tables match query
Table 1

No description provided.

Table 2

POSSIBLE EVIDENCE FOR OMEGA(1670) RESONANCE.


MULTI - HADRON PRODUCTION IN E+ E- ANNIHILATION AT 1.45-GEV - 1.61-GEV center-of-mass ENERGY

Esposito, B. ; Marini, A. ; Pallotta, M. ; et al.
Lett.Nuovo Cim. 25 (1979) 5-12, 1979.
Inspire Record 145867 DOI 10.17182/hepdata.37370

None

2 data tables match query
Table 1

No description provided.

Table 2

No description provided.


Measurement on $\pi^+ \pi^- \pi^0 \pi^0$, $\pi^+ \pi^- \pi^+ \pi^- \pi^0$, $\pi^+ \pi^- \pi^+ \pi^- \pi^0 \pi^0$, $\pi^+ \pi^- \pi^+ \pi^- \pi^+ \pi^-$ Production Cross-sections in $e^+ e^-$ Annihilation at 1.45-{GeV} - 1.80-{GeV} Center-of-mass Energy

Esposito, B. ; Marini, A. ; Piano Mortari, Giovanni ; et al.
Lett.Nuovo Cim. 31 (1981) 445-452, 1981.
Inspire Record 170489 DOI 10.17182/hepdata.37329

None

3 data tables match query
Table 1

No description provided.

Table 2

CROSS SECTIONS FOR POSITIVE AND NEGATIVE G-PARITY FINAL STATES (EVEN AND ODD NUMBERS OF PIONS).

Table 3

No description provided.


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 match query
Table 1

No description provided.

Table 2

No description provided.


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.

1 data table match query
Table 2

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


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 match query
Table 1

No description provided.

Table 2

No description provided.