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Evidence for neutral B meson decays to omegaK*0
P Goldenzweig1, A J Schwartz, I Adachi
1University of Cincinnati, Cincinnati, Ohio 45221, USA.
Physical Review Letters
|December 31, 2008
Summary
Researchers studied the charmless vector-vector decay B0 to omega K*0 using data from the Belle detector. The study measured the branching fraction and polarization of this decay, finding a significant nonresonant component.
Area of Science:
- Particle Physics
- High-Energy Physics
- Experimental Physics
Background:
- Investigating rare B meson decays provides crucial insights into the Standard Model of particle physics.
- Understanding vector-meson decays like B0 to omega K*0 helps probe fundamental interactions and search for new physics.
- Previous studies have explored various B meson decay modes, but specific modes like B0 to omega K*0 require further detailed analysis.
Purpose of the Study:
- To measure the branching fraction of the charmless vector-vector decay B0 to omega K*0.
- To perform a helicity analysis of the omega and K*0 vector mesons in this decay.
- To measure the nonresonant branching fraction in the B0 to omega K+pi(-) decay channel.
Main Methods:
- Analysis of 657 x 10^6 BBbar pairs collected by the Belle detector at the KEKB e+e- collider.
- Selection and reconstruction of the B0 --> omega K*0 decay channel.
- Helicity analysis to determine the polarization states of the vector mesons.
Main Results:
- The branching fraction for B0 to omega K*0 was measured to be (1.8 ± 0.7(stat) ± 0.3(syst)) x 10^-6 with a 3.0 sigma significance.
- The longitudinal polarization fraction fL for B0 to omega K*0 was found to be 0.56 ± 0.29(stat) -0.08(+0.18)(syst).
- A significant nonresonant branching fraction of (5.1 ± 0.7(stat) ± 0.7(syst)) x 10^-6 was measured for B0 to omega K+pi(-) in the specified K pi mass range, with a 9.5 sigma significance.
Conclusions:
- The study successfully measured the branching fraction and polarization of the B0 to omega K*0 decay.
- The results provide important data for theoretical models of B meson decays.
- The significant nonresonant component in the related channel indicates complex dynamics in B meson decays.
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