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New physics in rare B decays after Moriond 2021
Wolfgang Altmannshofer1, Peter Stangl2
1Department of Physics and Santa Cruz Institute for Particle Physics, University of California, Santa Cruz, 1156 High Street, Santa Cruz, CA 95064 USA.
The European Physical Journal. C, Particles and Fields
|November 8, 2021
Summary
Anomalies in rare B decays persist. Updated global analysis with new data and improved theory uncertainties shows muon-specific Wilson coefficients offer an excellent description of experimental results.
Area of Science:
- High Energy Physics
- Particle Physics
- Quantum Field Theory
Background:
- Anomalies in rare B decays suggest potential deviations from the Standard Model.
- Previous analyses have indicated tensions, necessitating updated investigations with the latest experimental data.
Purpose of the Study:
- To present an updated global analysis of rare B decays.
- To incorporate recent experimental results and improve the treatment of theoretical uncertainties.
- To investigate the role of Wilson coefficients for four-fermion contact interactions.
Main Methods:
- Global analysis of rare B decay data.
- Inclusion of the latest experimental measurements for B -> K* mu mu and B -> K mu mu branching ratios.
- Qualitative improvement in the treatment of theoretical uncertainties.
- Fitting Wilson coefficients for four-fermion contact interactions.
Main Results:
- Muon-specific Wilson coefficients (C9 or C9') provide an excellent description of the data.
- Considering theoretically clean observables, muon-specific C9 or C9' show significant improvement over the Standard Model.
- Updated combination of ATLAS, CMS, and LHCb data on branching ratios incorporating non-Gaussian likelihoods.
Conclusions:
- The anomalies in rare B decays are persistent and provide strong hints for new physics.
- Muon-specific Wilson coefficients are favored by the current experimental data.
- Predictions for lepton flavor universality observables and CP asymmetries are provided for future testing.
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