Arends, H.-J
E+ E- Scattering
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MASSES, WIDTHS, AND LEPTONIC WIDTHS OF THE HIGHER UPSILON RESONANCES

Lovelock, D.M.J. ; Horstkotte, J.E. ; Klopfenstein, C. ; et al.
Phys.Rev.Lett. 54 (1985) 377-380, 1985.
Inspire Record 215716 DOI 10.17182/hepdata.20355

The masses, total widths, and leptonic widths of three triplet s-wave bb¯ states ϒ(4S), ϒ(5S), and ϒ(6S) are determined from measurements of the e+e− annihilation cross section into hadrons for 10.55<W<11.25 GeV. The resonances are identified from potential model results and their properties are obtained with the help of a simplified coupled-channels calculation. We find M(4S)=10.577 GeV, Γ(4S)=25 MeV, Γee(4S)=0.28 keV; M(5S)=10.845 GeV, Γ(5S)=110 MeV, Γee(5S)=0.37 keV; M(6S)=11.02 GeV, Γ(6S)=90 MeV, Γee(6S)=0.16 keV.

1 data table
Table 1

VISIBLE CROSS SECTION INTO HADRONS.


Electron-positron interactions at high energies

Bartoli, B. ; Felicetti, F. ; Ogren, H. ; et al.
Phys.Rev.D 6 (1972) 2374-2404, 1972.
Inspire Record 83098 DOI 10.17182/hepdata.22258

The results of an experiment performed at Adone, the 2×1.5-GeV e+e− Frascati storage ring, are presented. During ∼ 1500 hours of running time a total of 5164 electron-positron elastic scattering events (integrated luminosity L=3.5×1035 cm−2) and 605 noncoplanar events from the reaction e+e−→a±+b±+anything (effective integrated luminosity L=2.5×1035 cm−2) have been collected at c.m. energies ranging from 1.4 to 2.4 GeV. Over the energy range explored (1.4-2.4 GeV), corresponding to an average q2 ranging from 0.8 to 2.4 (GeV/c)2, the yield of wide-angle (60°<θ<120°) electron-positron elastic scattering events is found to be in good agreement with the predictions of quantum electrodynamics (QED) (R=σexpσQED=1.05±0.04). The noncoplanar events appear to be of a hadronic nature and are produced with a much higher cross section than predicted on the basis of ρ, ω, φ dominance at these energies. The total cross section for the reaction e+e−→a±b±+anything shows a rapid increase to ∼ 90 nb between 1.0 and 1.5 GeV and falls off slowly to ∼ 50 nb at 2.4 GeV. Cross sections for some of the channels contributing to this multihadron process (e+e−→π+π−π+π−, e+e−→π+π−π+π−+neutrals, e+e−→3π+3π−) have been determined and are reported.

2 data tables
Table 1

DATA VALUES MEASURED FROM GRAPH IN JOURNAL.

Table 2

VALUES OF R CALCULATED FROM TOTAL CROSS SECTION.


Evidence for a Narrow Resonance at 10.01-GeV in electron-Positron Annihilations

Darden, C.W. ; Hasemann, H. ; Krolzig, A. ; et al.
Phys.Lett.B 78 (1978) 364-365, 1978.
Inspire Record 131898 DOI 10.17182/hepdata.27427

We observe evidence for a secon narrow resonance in the reation e + e − → hadrons at √s around 10 GeV using the DASP detector at the DORIS storage ring. The mass of the resonance is (10.01 ± 0.02) GeV; its width is in agreement with the storage ring resolution of ≈ 9 MeV. From the integrated cross section, an electronic width of Λ ee = (0.35 ± 0.14) KeV is derived.

1 data table
Table 1

No description provided.


Observation of a Narrow Resonance at 9.46-GeV in electron-Positron Annihilations

Darden, C.W. ; Hasemann, H. ; Krolzig, A. ; et al.
Phys.Lett.B 76 (1978) 246, 1978.
Inspire Record 130052 DOI 10.17182/hepdata.27447

We observe a narrow resonance in the reaction e + e − → hadrons using the DASP detector at the DORIS storage ring. The mass is found to be (9.46 ± 0.01) GeV and the observed width is compatible with the storage ring resolution of ±8 MeV. The energy-integrated cross section results in an electronic width Γ ee = (1.3 ± 0.4) keV.

1 data table
Table 1

VISIBLE HADRONIC TOTAL CROSS SECTION.


STUDY OF THE UPSILON (9.46) MESON IN ELECTRON - POSITRON ANNIHILATIONS

Darden, C.W. ; Hasemann, H. ; Krolzig, A. ; et al.
Phys.Lett.B 80 (1979) 419-422, 1979.
Inspire Record 145168 DOI 10.17182/hepdata.27358

New data for the reaction e + e − →ϒ(9.46) have been obtained using the DASP detector at the DORIS storage ring. The electronic width Γ ee is (1.5±0.4) keV. The branching ratio for the decay into muon pairs is (2.5 ± 2.1)%. Energy spectra for inclusive production of hadrons are given.

2 data tables
Table 1

VISIBLE HADRONIC TOTAL CROSS SECTION.

Table 2

INVARIANT INCLUSIVE PRODUCTION CROSS SECTION E*D3(SIG)/DP**3 BOTH ON AND OFF THE UPSILON(9.46) RESONANCE. NO SIGNIFICANT DIFFERENCE IN EXPONENTIAL SLOPE AS A FUNCTION OF PARTICLE ENERGY E(P=3).


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.


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.


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.


Multiparticle production from e+ e- interactions at high energy

Bartoli, B. ; Felicetti, F. ; Ogren, H. ; et al.
Phys.Lett.B 36 (1971) 598-602, 1971.
Inspire Record 69109 DOI 10.17182/hepdata.28392

Measurements of multiple particle production at ADONE, the Frascati e + e − storage ring, have been carried out at C.M. energies 1.4 GeV to 2.4 GeV. The hadronic nature of the observed particles is discussed and a lower limit of 30 nbarn set for the total multiparticle cross section.

1 data table
Table 1

LOWER LIMIT FOR PRODUCTION OF AT LEAST TWO CHARGED HADRONS.