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Carrier Lifetime Measurements in Semiconductors through the Microwave Photoconductivity Decay Method
Published on: April 18, 2019
Amplitude analysis of the B+/--->phiK*(892)+/- decay.
1Laboratoire de Physique des Particules, IN2P3/CNRS et Université de Savoie, F-74941 Annecy-Le-Vieux, France.
Physical Review Letters
|February 1, 2008
Summary
This study analyzes B+ decays, measuring key parameters like amplitude fractions and CP violation sensitivity. Results indicate a significant helicity-plus amplitude from an unidentified source.
Area of Science:
- Particle Physics
- High Energy Physics
- Quantum Chromodynamics
Background:
- The B+ meson decay to phi(1020)K*(892)+/- provides a rich system for studying fundamental symmetries.
- Understanding decay dynamics is crucial for testing the Standard Model of particle physics.
Purpose of the Study:
- To perform a detailed amplitude analysis of the B+/--->phi(1020)K*(892)+/- decay.
- To measure amplitude fractions, branching fractions, strong phases, and CP violation parameters.
- To resolve ambiguities in phase determination using Kpi invariant mass dependence.
Main Methods:
- Amplitude analysis of approximately 384 million BBbar pairs recorded by the BABAR detector.
- Utilizing the interference between different Kpi components (JP=1(-) and 0+) to resolve discrete ambiguities.
- Simultaneous measurement of twelve decay parameters.
Main Results:
- Measured longitudinal amplitude fraction (fL) = 0.49 ± 0.05 ± 0.03.
- Measured parity-odd transverse amplitude fraction (f perpendicular) = 0.21 ± 0.05 ± 0.02.
- Strong phase measurements suggest a significant helicity-plus amplitude from an unknown source.
Conclusions:
- The amplitude analysis provides precise measurements of decay parameters.
- The observed helicity-plus amplitude indicates potential new physics or unmodeled contributions.
- Further investigation is needed to identify the source of this unexpected amplitude.
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