Comprehensive Analysis of the B^{0}→K^{*0}μ^{+}μ^{-} Decay

Area of Science:

• High-energy particle physics
• Experimental particle physics
• Quantum chromodynamics

Background:

• The Standard Model (SM) of particle physics successfully describes fundamental particles and forces.
• Deviations from SM predictions in B meson decays could indicate new physics.
• Previous analyses of B^{0}→K^{*0}μ^{+}μ^{-} decay hinted at discrepancies with SM predictions.

Purpose of the Study:

• To precisely measure angular observables and branching fractions for the B^{0}→K^{*0}μ^{+}μ^{-} decay.
• To search for deviations from the Standard Model in these measurements.
• To present, for the first time, the full set of observables for the K^{+}π^{-} S-wave contribution.

Main Methods:

• Analysis of proton-proton collision data from the LHCb experiment.
• Determination of CP-averaged and CP-asymmetric angular observables in bins of dimuon invariant mass squared.
• Measurement of branching fractions relative to the B^{0}→J/ψK^{+}π^{-} decay.
• Inclusion of effects from muon mass and the K^{+}π^{-} S-wave contribution.

Main Results:

• CP-asymmetry observables were measured and found to show no significant deviations from zero.
• CP-averaged observables and branching fractions were measured, continuing a pattern of tension with Standard Model predictions.
• The full set of observables for the K^{+}π^{-} S-wave contribution was presented for the first time.

Conclusions:

• The results for CP-asymmetries are consistent with the Standard Model.
• The observed tensions in CP-averaged observables and branching fractions warrant further investigation.
• This comprehensive analysis contributes to the ongoing search for physics beyond the Standard Model.