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Setting Limits on Supersymmetry Using Simplified Models
Published on: November 15, 2013
First measurement of the form factors in the decays D0 → ρ- e+ ν(e) and D+ → ρ0 e+ ν(e)
S Dobbs1, Z Metreveli, K K Seth
1Northwestern University, Evanston, Illinois 60208, USA.
Physical Review Letters
|April 16, 2013
Summary
This study precisely measures form factors for D meson decays, crucial for determining the up quark coupling constant |V(ub)|. These findings enhance our understanding of fundamental particle physics and weak interactions.
Area of Science:
- Particle Physics
- Quantum Chromodynamics
- Hadron Spectroscopy
Background:
- The up quark coupling constant |V(ub)| is a fundamental parameter in the Standard Model.
- Precise determination of |V(ub)| requires accurate form factors from B and D meson decays.
- Previous measurements of D meson decay form factors had limited precision.
Purpose of the Study:
- To measure form factors for D0 → ρ- e+ ν(e) and D+ → ρ0 e+ ν(e) decays for the first time.
- To improve the precision of branching fraction measurements for these decays.
- To provide essential data for extracting the up quark coupling constant |V(ub)|.
Main Methods:
- Analysis of the complete CLEO-c ψ(3770) → DD event sample (818 pb⁻¹).
- Utilized a four-dimensional unbinned maximum likelihood fit.
- Measured form factor ratios and branching fractions for D meson semileptonic decays.
Main Results:
- First-time measurement of form factors for D0 → ρ- e+ ν(e) and D+ → ρ0 e+ ν(e).
- Precise determination of form factor ratios: V(0)/A1(0)=1.48±0.15±0.05 and A2(0)/A1(0)=0.83±0.11±0.04.
- Improved precision for branching fraction measurements, including D+ → ω e+ ν(e).
Conclusions:
- The measured form factors and branching fractions provide crucial inputs for |V(ub)| determination.
- Results are consistent with Cabibbo-Kobayashi-Maskawa unitarity.
- This study significantly advances the precision of parameters relevant to weak interactions.
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