Branching fraction measurements of B → ηc K decays
Physical Review D - Particles, Fields, Gravitation and Cosmology 70:1 (2004)
Abstract:
We study the decays B+ → ηcK+ and B0 → ηcK0, where the ηc is reconstructed in the KS0K ±π∓ and K+K- π0 decay modes. Results are based on a sample of 86 B B̄ pairs collected with the BABAR detector at the SLAC e+e- B Factory. We measure the product of branching fractions B(B+ → ηcK+) ×B(ηc→KK̄π)= (7.40±0.50±0.70)×10-5 and B(B 0→ηcK0) ×B(ηc→KK̄π)=(6.48±0.85±0.71) ×10-5, where the first error is statistical and the second is systematic, In addition, we search for B → ηcK events with ηc→2(K+K-) and ηc→ φφ and determine the ηc decay branching fraction ratios B(ηc →(K+K-)) /B(ηc→KK̄π)=(2.3±0.7±0.6) ×10-2 and B(ηc→φφ) /B(ηc→KK̄π)=(5.5±1.4±0.5) ×10-2.Determination of the e+e- → γγ (γ) cross-section at LEP 2
European Physical Journal C 37:4 (2004) 405-419
Abstract:
A test of the benchmark QED process e+e- → γγ(γ) is reported, using the data collected with the DELPHI detector at LEP 2. The data analysed were recorded at centre-of-mass energies ranging from 161 GeV to 208 GeV and correspond to a total integrated luminosity of 656.4 pb-1. The Born cross-section for the process e +e- → γγ(γ) was determined, confirming the validity of QED at the highest energies ever attained in electron-positron collisions. Lower limits on the parameters of a number of possible deviations from QED, predicted within theoretical frameworks expressing physics beyond the Standard Model, were derived. © Springer-Verlag/ Società Italiana di Fisica 2004.Erratum: Search for supersymmetric particles assuming R-parity non-conservation in e+e- collisions at √s = 192 to 208 GeV (The European Physical Journal C (2004) 36 (1-23) DOI: 10.1140/epjc/s2004-01881-6)
European Physical Journal C 37:1 (2004) 129-131
Erratum: b-tagging in DELPHI at LEP (European Physical Journal C (2004) 32 (185-208) DOI 10.1140/epjc/s2003-01441-8)
European Physical Journal C 32:2 (2004) 299-301
Limits on the decay-rate difference of neutral B mesons and on CP, T, and CPT violation in B0B̄0 oscillations
Physical Review D - Particles, Fields, Gravitation and Cosmology 70:1 (2004)