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First search for the flavor changing neutral current decay D0-->gammagamma
Physical Review Letters
|April 12, 2003
Summary
Researchers searched for the rare D0 to gamma gamma decay. No significant signal was observed, setting upper limits on this flavor changing neutral current process.
Area of Science:
- Particle Physics
- High Energy Physics
- Quantum Chromodynamics
Background:
- Flavor changing neutral current (FCNC) processes are rare in the Standard Model.
- The decay D0 to gamma gamma is highly suppressed in the Standard Model.
- Experimental searches for such decays provide stringent tests of the Standard Model and probe for new physics.
Purpose of the Study:
- To search for the flavor changing neutral current (FCNC) decay D0 to gamma gamma.
- To set upper limits on the branching fraction of D0 to gamma gamma.
- To constrain new physics models beyond the Standard Model.
Main Methods:
- Analysis of 13.8 fb^-1 of data collected with the CLEO detector at or just below the Upsilon(4S) resonance.
- Reconstruction of D0 mesons and their decays.
- Statistical analysis to set 90% confidence level upper limits on the branching fraction.
Main Results:
- No significant signal for the decay D0 to gamma gamma was observed.
- A 90% confidence level upper limit on the branching fraction B(D0 to gamma gamma) was determined to be less than 2.9 x 10^-5.
- An upper limit on the ratio of branching fractions B(D0 to gamma gamma)/B(D0 to pi(0)pi(0)) was found to be less than 0.033.
Conclusions:
- The experimental search places stringent constraints on the branching fraction of the rare decay D0 to gamma gamma.
- The results are consistent with Standard Model predictions and disfavor certain new physics scenarios that enhance FCNC processes.
- Future experiments with higher luminosity and improved resolution will be able to further probe this decay mode.
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