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Measurement of the lifetime difference in the B0(s) system
V M Abazov1, B Abbott, M Abolins
1Joint Institute for Nuclear Research, Dubna, Russia.
Physical Review Letters
|December 31, 2005
Summary
This study analyzes B0(s) meson decays into J/psi and phi. Key findings include the CP-odd fraction and precise measurements of the B0(s) lifetime and width difference, crucial for particle physics understanding.
Area of Science:
- Particle Physics
- High Energy Physics
- Quantum Mechanics
Background:
- The B0(s) meson system exhibits complex behavior due to particle-antiparticle mixing.
- Understanding decay properties is essential for testing the Standard Model of particle physics.
Purpose of the Study:
- To precisely measure the CP-odd fraction in the B0(s) --> J/psiphi decay.
- To determine the average lifetime and relative width difference of the B0(s) system.
- To investigate the ratio of B0(s) to B0 meson lifetimes.
Main Methods:
- Analysis of B0(s) --> J/psiphi decay modes.
- Time-dependent measurements to extract decay parameters.
- Inclusion of world average data from semileptonic decays for enhanced precision.
Main Results:
- CP-odd fraction (Rperpendicular) determined as 0.16 ± 0.10 (stat) ± 0.02 (syst).
- Average B0(s) lifetime (tau(B0(s))) measured as 1.39(+0.13)(-0.16)(stat)(+0.01)(-0.02)(syst) ps.
- Relative width difference (DeltaGamma/Gamma) found to be 0.24(+0.28)(-0.38)(stat)(+0.03)(-0.04)(syst).
- Constrained values: tau(B0(s)) = 1.39 ± 0.06 ps and DeltaGamma/Gamma = 0.25(+0.14)(-0.15).
- Lifetime ratio tau(B0(s))/tau(B0) = 0.91 ± 0.09(stat) ± 0.003(syst).
Conclusions:
- The study provides precise measurements of fundamental parameters for the B0(s) meson.
- Results contribute to a deeper understanding of CP violation and weak interactions.
- The findings offer valuable data for theoretical models in particle physics.
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