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Evidence for charged B meson decays to a1+/-(1260)pi0 and a1(0)(1260)pi+/-
1Laboratoire de Physique des Particules, IN2P3/CNRS et Université de Savoie, F-74941 Annecy-Le-Vieux, France.
Physical Review Letters
|February 1, 2008
Summary
Researchers measured branching fractions for B meson decays into a1(1260) and pi mesons. These findings contribute to understanding B meson decays and the properties of the a1(1260) resonance.
Area of Science:
- Particle Physics
- High Energy Physics
- Experimental Physics
Background:
- B mesons are fundamental particles in the Standard Model, and their decays provide insights into fundamental forces.
- The a1(1260) is a broad meson resonance whose properties are not fully understood.
- Understanding these decays is crucial for testing theoretical models of particle interactions.
Purpose of the Study:
- To measure the branching fractions for two specific B meson decays: B+/- --> a1+/-(1260)pi0 and B+/- --> a10(1260)pi+/-.
- To determine the contribution of these decays to the overall B meson decay modes.
- To provide precise experimental data for theoretical calculations and comparisons.
Main Methods:
- Analysis of a large dataset of 232 million BBbar pairs collected from e+e- annihilation at the Upsilon(4S) resonance.
- Reconstruction of B meson decays involving the a1(1260) resonance decaying into three pions.
- Statistical analysis to determine branching fractions and their associated uncertainties (statistical and systematic).
Main Results:
- Measured branching fraction for B+/- --> a1+/-(1260)pi0, with a1+/-(1260) --> pi-pi+pi+-, is (13.2 +/- 2.7 +/- 2.1) x 10^-6, with a significance of 4.2 sigma.
- Measured branching fraction for B+/- --> a10(1260)pi+/-, with a10(1260) --> pi-pi+pi0, is (20.4 +/- 4.7 +/- 3.4) x 10^-6, with a significance of 3.8 sigma.
- These results represent the first measurements of these specific branching fractions.
Conclusions:
- The study successfully measured the branching fractions for the B meson decays into a1(1260) and pi mesons.
- The observed decays provide valuable experimental data for the study of hadronic B decays and the nature of the a1(1260) resonance.
- Future theoretical and experimental work can utilize these precise measurements.
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