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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 Currents in e+ e- Collisions at s**(1/2)=29-GeV

Levi, M.E. ; Blocker, C.A. ; Strait, J. ; et al.

Phys.Rev.Lett. 51 (1983) 1941, 1983.

Inspire Record 191845 DOI 10.17182/hepdata.3281

The differential cross sections for lepton pair production in e+e− annihilation at 29 GeV have been measured and found to be in good agreement with the standard model of the electroweak interaction. With the assumption of e−μ−τ universality, the weak neutral-current couplings are determined to be ga2=0.23±0.05 and gv2=0.03±0.04.

8 data tables

Table 1

Numerical values supplied by M.Levi.

Table 2

Data requested from authors.

Table 3

Extrapolated to full angular range.

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rivet Analysis
Differential Cross-sections for $\gamma \gamma \to p \bar{p}$ in the Center-of-mass Energy Range From 2.0-{GeV} to 3.1-{GeV}

The TASSO collaboration Althoff, M. ; Braunschweig, W. ; Gather, K. ; et al.

Phys.Lett.B 130 (1983) 449-453, 1983.

Inspire Record 191417 DOI 10.17182/hepdata.6654

Exclusive production of proton-antiproton pairs by two photon scattering at CM energies between 2.0 GeV and 3.1 GeV has been measured with the TASSO detector at the e + e − storage ring PETRA. The angular distribution is flat within the accepted CM angular range | cos Θ ∗ |⩽0.7 . The integrated cross section (| cos Θ ∗ |⩽0.6) drops from about 4 nb at 2 GeV to less than 0.5 nb above 3 GeV. For the two-photon production of the η c (2984) and its subsequent decay into proton-antiproton the upper limit Γ(η c →γγ)· B (η c → p p )<0.32 keV (95% CL) is found.

5 data tables

Table 1

No description provided.

Table 2

No description provided.

Table 3

UPPER LIMIT FOR THE PRODUCT OF THE ETA/C --> GAMMA GAMMA WIDTH AND THE BRANCHING RATIO OF ETA/C --> P AP IS DETERMINED TO BE 0.32 KEV WITH 90 PCT CL.

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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.

A STUDY OF e+ e- ANNIHILATION IN THE 1400-MeV TO 2250-MeV ENERGY RANGE WITH THE MAGNETIC DETECTOR DM2 AT DCI

Augustin, J.E. ; Ayach, L. ; Calcaterra, A. ; et al.

LAL-83-21, 1983.

Inspire Record 192321 DOI 10.17182/hepdata.13242

None

5 data tables

Table 1

ASSUMING ABS(GE)=ABS(GM).

Table 2

No description provided.

Table 3

No description provided.

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rivet Analysis
>A Measurement of $e^+ e^- \to \bar{p} p$ for 1975-{MeV} $\le \sqrt{s} \le$ 2250-{MeV}

Bisello, D. ; Limentani, S. ; Nigro, M. ; et al.

Nucl.Phys.B 224 (1983) 379, 1983.

Inspire Record 190558 DOI 10.17182/hepdata.33935

The e + e − → p p cross section has been measured in the energy interval (1975 ⩽ 2 E ⩽ 2250) MeV for |cos θ | < 0.7. The measurement is based on ∼ 100 events, thus improving by a factor 3 on the previous existing statistics in this energy interval. The form factor | G | 2 is given as a function of energy under the assumption | G E | = | G M |. We also give the first measurement of the differential cross section, averaged over the energy interval, and estimate the ratio G M |/| G E | from it.

3 data tables

Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

A Model Independent Second Order Determination of the Strong Coupling Constant $\alpha^- s$

Adeva, B. ; Barber, D.P. ; Becker, U. ; et al.

Phys.Rev.Lett. 50 (1983) 2051, 1983.

Inspire Record 189724 DOI 10.17182/hepdata.3086

With use of the MARK-J detector at s=34.7 GeV 21 000 e+e−→hadron events have been collected. By measurement of the asymmetry in angular energy correlations the strong coupling constant αs=0.13±0.01 (statistical)±0.02 (systematic) is determined, in complete second order, and independent of the fragmentation models and QCD cutoff values used.

2 data tables

Table 1

DATA REQUESTED FROM THE AUTHORS.

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.

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.