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Measurement of the decay B(-) ---> D(*0)e(-)nu[overline](e)
B Aubert1, M Bona, Y Karyotakis
1Laboratoire de Physique des Particules, IN2P3/CNRS et Université de Savoie, Annecy-Le-Vieux, France.
Physical Review Letters
|July 23, 2008
Summary
Researchers analyzed B meson decays to D* mesons using BABAR detector data. They determined key parameters for B meson decays, contributing to understanding weak interactions and the CKM matrix element |V(cb)|.
Area of Science:
- High Energy Physics
- Particle Physics
- Quantum Chromodynamics
Background:
- The Standard Model of particle physics describes fundamental forces and particles.
- Understanding B meson decays provides insights into the weak interaction and the Cabibbo-Kobayashi-Maskawa (CKM) matrix.
- Precise measurements of B meson decays are crucial for testing the Standard Model and searching for new physics.
Purpose of the Study:
- To reconstruct and analyze B(-) ---> D(*0)e(-)nu[overline](e) decays.
- To determine the form factor parameters rhoA(1)(2) and F(1) for these decays.
- To measure the branching fraction of B(-) ---> D(*0)e(-)nu[overline](e) and constrain the CKM matrix element |V(cb)|.
Main Methods:
- Analysis of 226 x 10^6 BB[overline] events collected with the BABAR detector at the SLAC e(+)e(-) PEP-II storage rings.
- Reconstruction of B(-) ---> D(*0)e(-)nu[overline](e) decays via the chain D(*0) --> D(0)pi(0) and D(0)-->K(-)pi(+).
- Utilizing the differential decay rate dependence on w (four-velocity dot product) and the Caprini et al. form factor description.
Main Results:
- Determination of the form factor parameter rhoA(1)(2) = 1.16 +/- 0.06 +/- 0.08.
- Measurement of F(1)|V(cb)| = (35.9 +/- 0.6 +/- 1.4) x 10^-3.
- Branching fraction B(B(-) --> D(*0)e(-)nu[overline](e)) = (5.56 +/- 0.08 +/- 0.41)%.
Conclusions:
- The study provides precise measurements of key parameters in B meson decays.
- The results contribute to a more accurate determination of the CKM matrix element |V(cb)|.
- These findings offer valuable data for theoretical calculations in particle physics and potential searches for physics beyond the Standard Model.
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