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Observation of the decay Omega(0)(c)-->Omega(-)e(+)nu(e)
Physical Review Letters
|October 26, 2002
Summary
Researchers observed the Omega(0)(c) charm baryon decaying into Omega(-) and an electron-neutrino pair. This marks the first significant observation of this specific Omega(0)(c) decay in electron-positron collisions.
Area of Science:
- Particle Physics
- High-Energy Physics
- Quantum Chromodynamics
Background:
- The Omega(0)(c) is a charm baryon with a css quark configuration.
- Understanding baryon decays provides insights into fundamental forces.
- Previous studies lacked statistically significant observations of specific Omega(0)(c) decay modes in e(+)e(-) annihilation.
Purpose of the Study:
- To observe and characterize the decay of the Omega(0)(c) baryon.
- To measure the branching fraction and cross-section for the Omega(0)(c) --> Omega(-)e(+)nu(e) decay.
- To investigate rare baryon decay mechanisms.
Main Methods:
- Data collected using the CLEO detector at the Cornell Electron Storage Ring.
- Analysis focused on the specific decay channel Omega(0)(c) --> Omega(-)e(+)nu(e).
- Statistical methods employed to confirm signal significance and measure properties.
Main Results:
- Observed a signal of 11.4+/-3.8 events for Omega(0)(c) --> Omega(-)e(+)nu(e) with a background fluctuation probability of 7.6x10(-5).
- Measured the product of branching fraction and cross-section: B(Omega(0)(c)-->Omega(-)e(+)nu(e)).sigma(e(+)e(-)-->Omega(0)(c)X) = (42.2+/-14.1+/-5.7) fb.
- Determined the ratio of decay widths: R = [Gamma(Omega(0)(c)-->Omega(-)pi(+))]/[Gamma(Omega(0)(c)-->Omega(-)enu(e))] = 0.41+/-0.19+/-0.04.
Conclusions:
- This is the first statistically significant observation of an individual Omega(0)(c) decay mode in e(+)e(-) annihilation.
- The observed decay provides the first example of a baryon decaying via beta emission without first-generation quarks.
- Results contribute to the understanding of weak interactions in heavy baryons.
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