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Studies of the decay B+/- -->D(CP)K+/-
Physical Review Letters
|April 12, 2003
Summary
Researchers studied the Cabibbo-suppressed decay of B+ mesons into D(CP)K+-. They measured branching fraction ratios and partial rate asymmetries, providing insights into particle physics.
Area of Science:
- High Energy Physics
- Particle Physics
- Quantum Chromodynamics
Background:
- The B+ meson decay provides a sensitive probe for New Physics beyond the Standard Model.
- Understanding Cabibbo-suppressed decays is crucial for testing theoretical predictions.
Purpose of the Study:
- To study the Cabibbo-suppressed decay B+ -> D(CP)K+-.
- To measure branching fraction ratios relative to Cabibbo-favored decays.
- To extract partial rate asymmetries for these decays.
Main Methods:
- Analysis of a 29.1 fb^-1 data sample collected by the Belle detector at the KEKB asymmetric e+e- collider.
- Utilizing the Upsilon(4S) resonance for B meson production.
- Measurement of branching fraction ratios and partial rate asymmetries.
Main Results:
- Measured B(B+ -> D1K+-)/B(B+ -> D1pi+-) = 0.125 ± 0.036 ± 0.010 for the CP=+1 eigenstate.
- Measured B(B+ -> D2K+-)/B(B+ -> D2pi+-) = 0.119 ± 0.028 ± 0.006 for the CP=-1 eigenstate.
- Extracted partial rate asymmetries A(1) = 0.29 ± 0.26 ± 0.05 and A(2) = -0.22 ± 0.24 ± 0.04.
Conclusions:
- The measured branching fraction ratios and asymmetries provide constraints on theoretical models.
- These results contribute to the ongoing effort to understand CP violation in the B meson system.
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