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Search for CP violation in D± meson decays to ϕπ±
M Starič1, H Aihara, K Arinstein
1J. Stefan Institute, Ljubljana.
Physical Review Letters
|March 10, 2012
Summary
This study searched for CP violation in D meson decays. No evidence for direct CP violation was found in Cabibbo-suppressed decays, improving search sensitivity by over five times.
Area of Science:
- Particle Physics
- High Energy Physics
- Quantum Chromodynamics
Background:
- CP violation is a key concept in particle physics, explaining matter-antimatter asymmetry.
- Cabibbo-suppressed decays offer a sensitive probe for new physics beyond the Standard Model.
Purpose of the Study:
- To search for direct CP violation in charged D meson decays.
- To measure CP-violating asymmetries in Cabibbo-suppressed D+ decays.
Main Methods:
- Utilized 955 fb⁻¹ of data from the Belle detector.
- Measured asymmetries in D+→ϕπ+ decays within the ϕ resonance region.
- Compared Cabibbo-suppressed D+ decays with Cabibbo-favored D(s)+ decays.
Main Results:
- Obtained A(CP)(D+→ϕπ+) = (+0.51 ± 0.28 ± 0.05)%.
- Achieved a factor of 5 improvement in sensitivity compared to previous searches.
- Found no evidence for direct CP violation.
Conclusions:
- The search for direct CP violation in these D meson decays yielded no significant signal.
- The results place constraints on new physics contributions to these processes.
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