Limits on Spin 0 Bosons in $e^+ e^-$ Annihilation Up to 45.2-{GeV} Center-of-mass Energy

The CELLO collaboration Behrend, H.J. ; Burger, J. ; Criegee, L. ; et al.
Phys.Lett.B 140 (1984) 130-136, 1984.
Inspire Record 199851 DOI 10.17182/hepdata.30547

We have studied the reactions e + e − → e + e − , e + e − → γγ , e + e − → μ + μ − , and e + e − → τ + τ − in the centre-of-mass (CM) energy range from 39.8 to 45.2 GeV using the CELLO detector at PETRA. Upper limits on the partial widths for new spin 0 bosons with masses both within and above the energy range covered are determined. No evidence for contributions of such new particles has been observed up to the highest PETRA energies in a model independent way. Under the assumptions of recently suggested models relating the existence of spin 0 bosons to the radiative width Γ τ of the Z 0 we exclude such bosons at the 95% confidence level for masses below the Z 0 -mass if Γ τ > 20 MeV.

2 data tables

No description provided.

Figure actually gives the 95 PCT CL upper limits of the coupling constants for each process as a function of the mass of the intermediate spin zero boson.


Investigation of Two Photon Final States in $e^+ e^-$ Annihilation at $\sqrt{s}=34$.2-{GeV}

The CELLO collaboration Behrend, H.J. ; Chen, C. ; Fenner, H. ; et al.
Phys.Lett.B 123 (1983) 127-132, 1983.
Inspire Record 182585 DOI 10.17182/hepdata.30780

Two photon final states in e + e − annihilation have been analyzed at CM energies around 34 GeV. Good agreement with QED is observed. Lower limits for the QED cutoff parameters of Λ + > 59 GeV and Λ - > 44 GeV are determined. A search for two photons with missing energy yields an upper limit for the production of neutral particles which decay into a photon and a non-interacting particle. Constraints on the mass and the coupling strength of supersymmetric photinos are discussed.

2 data tables

Cross section for ABS(cos(theta)) <0.85.

No description provided.


Measurement of $e^+ e^- \to e^+ e^-$ and $e^+ e^- \to \gamma \gamma$ at Energies Up to 36.7-{GeV}

The CELLO collaboration Behrend, H.J. ; Chen, C. ; Field, J. ; et al.
Phys.Lett.B 103 (1981) 148-152, 1981.
Inspire Record 165288 DOI 10.17182/hepdata.31169

The differential cross sections of the reactions e + e − → e + e − and e + e − → λλ are measured at energies between 33.0 and 36.7 GeV. The results agree with the predictions of quantum electrodynamics. A comparison with the standard model of electroweak interaction yields sin 2 θ W = 0.25 ± 0.13.

2 data tables

No description provided.

No description provided.