HEPData Search

Results are reported on a high statistics study of Bhabha scattering at 29 GeV in the polar angle region, |cos θ | < 0.55. The data are consistent with the standard model, and measure vector and axial-vector coupling constants of g v 2 = 0.03 ± 0.09 and g a 2 = 0.46±0.14. Limits on the QED-cutoff parameters are Λ + > 154 GeV and Λ - > 220 GeV. Lower limits on scale parameters of composite models are in the range 0.9–2.8 TeV. The partial width of a hypothetical spin-zero boson decaying to e + e − has an upper limit which varies from 6 to 57 MeV corresponding to a boson mass in the range 45–80 GeV/ c 2 .

1 data table match query

Table 1

No description provided.

The reactions $k^{+}d \to k^{+}d, k^{+}d \to k^{+}pn$ and $k^{+}d \to k^{0}pp$ at 3 Gev/$c$ with an investigation of $k^+n$ scattering

Buchner, K. ; Dehm, G. ; Geist, Walter M. ; et al.

Nucl.Phys.B 44 (1972) 110-124, 1972.

Inspire Record 75078 DOI 10.17182/hepdata.32864

As a partial result of an analysis of K + d interactions at 3 GeV/ c produced in the 81 cm Saclay bubble chamber, we present data on K + differential cross sections for the following reactions: K + d → K + d, K + d → K + pn, K + d → K 0 pp . A set of parameters describing the K + n elastic scattering has been obtained from a simulataneous fit, based on the Glauber model. to the three experimental differential cross sections and to the K + d total cross section, giving α n = 1.7 ± 0.5 GeV −2 for the slope α n of the differential cross section, and ρ n = −0.16 ± 0.3 for the ratio of the real to the imaginary part of the forward scattering amplitude. The D-wave function of the deuteron has been found to give a non-negligible contribution to the coherent reaction.

2 data tables match query

Table 1

No description provided.

Table 2

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Tests of the standard model and constraints on new physics from measurements of fermion pair production at 189-GeV at LEP

The OPAL collaboration Abbiendi, G. ; Ackerstaff, K. ; Alexander, G. ; et al.

Eur.Phys.J.C 13 (2000) 553-572, 2000.

Inspire Record 504989 DOI 10.17182/hepdata.49123

Cross-sections and angular distributions for hadronic and lepton pair final states in e+e- collisions at a centre-of-mass energy near 189 GeV, measured with the OPAL detector at LEP, are presented and compared with the predictions of the Standard Model. The results are used to measure the energy dependence of the electromagnetic coupling constant alpha_em, and to place limits on new physics as described by four-fermion contact interactions or by the exchange of a new heavy particle such as a sneutrino in supersymmetric theories with R-parity violation. A search for the indirect effects of the gravitational interaction in extra dimensions on the mu+mu- and tau+tau- final states is also presented.

3 data tables match query

Table 3

The cross sections for electron -pair production with various angular cuts.

Table 5

The forward-backward asymmetry in electron-pair production for cos(theta_e) <0.7.

Table 7

The angular distribution for electron-pair production. The errors include statistical and systematic effects combined.

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n-p Elastic Charge Exchange in the BeV Energy Region

New Results From Bhabha Scattering at 29-{GeV}

The reactions $k^{+}d \to k^{+}d, k^{+}d \to k^{+}pn$ and $k^{+}d \to k^{0}pp$ at 3 Gev/$c$ with an investigation of $k^+n$ scattering

Tests of the standard model and constraints on new physics from measurements of fermion pair production at 189-GeV at LEP