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Measurement of B(Ds{+}-->mu+nu(mu))
Physical Review Letters
|July 23, 2008
Summary
Researchers measured the D(s) meson
Area of Science:
- Particle Physics
- High-Energy Physics
- Experimental Physics
Background:
- The D(s) meson is a key probe for testing the Standard Model.
- Measuring its decay constant f(D(s)) provides insights into fundamental particle interactions.
- Previous measurements have uncertainties that limit precision tests.
Purpose of the Study:
- To precisely measure the branching fraction of the D(s) meson decaying into a muon and a neutrino.
- To determine the D(s) decay constant f(D(s)) with high accuracy.
- To contribute to precision tests of the Standard Model of particle physics.
Main Methods:
- Utilized a large dataset of 548 fb^-1 from the Belle experiment at the KEKB e+e- collider.
- Employed a full-reconstruction method by analyzing e+e- --> D(s)*DKX events.
- Reconstructed the D(s) momentum by analyzing the system recoiling against DKgammaX.
Main Results:
- Measured the branching fraction B(D(s)+ --> mu+ nu(mu)) = [6.44 +/- 0.76(stat) +/- 0.57(syst)] x 10^-3.
- Determined the D(s) decay constant f(D(s)) = [275 +/- 16(stat) +/- 12(syst)] MeV.
- Achieved high resolution in neutrino momentum for excellent background separation.
Conclusions:
- The precise measurement of B(D(s)+ --> mu+ nu(mu)) and f(D(s)) advances our understanding of heavy quark decays.
- This result provides a valuable input for future Standard Model precision tests.
- The employed full-reconstruction method demonstrates its effectiveness in high-energy physics experiments.
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