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First Physics Results at BABAR

Francesca Di Lodovico
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Abstract

The BABAR detector, which operates at the SLAC PEP-II asymmetric e^+e^- collider at energies near the Y(4S) resonance, started operation on the 26th of May 1999. We present the first study of sin2beta, with samples of B0 --> J/psi K0S and B0 --> psi(2S) K0S decays, using 9.0 fb-1 of data recorded between January and July 2000 at the Y(4S) resonance and 0.8 fb-1 recorded 40 MeV below the Y(4S) resonance. A preliminary result of sin2beta = 0.12+/-0.37 (stat) +/- 0.09 (syst) was obtained. Details of the analysis are given. Moreover, we present measurements of charged and neutral B meson lifetimes and B^0 B^0bar oscillation frequency.

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Francesca Di Lodovico. 2000-12-01. First Physics Results at BABAR. https://arxiv.org/abs/hep-ex/0012005

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