Observation of the B(s)(0)→η'η' Decay

Area of Science:

• Particle Physics
• High-Energy Physics
• Quantum Chromodynamics

Background:

• The B(s)(0) meson is a neutral B meson containing a strange quark.
• Understanding B meson decays provides insights into the Standard Model of particle physics.
• Previous studies have explored various B meson decay modes.

Purpose of the Study:

• To report the first observation of the B(s)(0)→η'η' decay.
• To measure the branching fraction of this decay mode.
• To measure charge asymmetries of related B meson decays as control channels.

Main Methods:

• Analysis of proton-proton collision data collected by the LHCb detector.
• Utilizing a data sample corresponding to 3.0 fb⁻¹ of integrated luminosity.
• Statistical analysis to determine signal significance and branching fraction.

Main Results:

• The B(s)(0)→η'η' decay is observed with a significance of 6.4 standard deviations.
• The branching fraction is measured as [3.31±0.64(stat)±0.28(syst)±0.12(norm)]×10⁻⁵.
• Charge asymmetries for B(±)→η'K(±) and B(±)→ϕK(±) are measured as (-0.2±1.3)% and (+1.7±1.3)%, respectively.

Conclusions:

• The results are consistent with theoretical predictions.
• This observation contributes to the understanding of rare B meson decays.
• The measured branching fraction and asymmetries provide valuable data for theoretical models.