The angular distribution of the flavor-changing neutral current decay B$^+$$\to$ K$^+\mu^+\mu^-$ is studied in proton-proton collisions at a center-of-mass energy of 8 TeV. The analysis is based on data collected with the CMS detector at the LHC, corresponding to an integrated luminosity of 20.5 fb$^{-1}$. The forward-backward asymmetry $A_{\mathrm{FB}}$ of the dimuon system and the contribution $F_{\mathrm{H}}$ from the pseudoscalar, scalar, and tensor amplitudes to the decay width are measured as a function of the dimuon mass squared. The measurements are consistent with the standard model expectations.
Figure 5a. Results of the $A_{FB}$ measurements in ranges of q2. 0 ≤ $F_{H}$ ≤ 3 and |$A_{FB}$| ≤ min(1, $F_{H}$/2).
Figure 5b. Results of the $F_{H}$ measurements in ranges of q2. 0 ≤ $F_{H}$ ≤ 3 and |$A_{FB}$| ≤ min(1, $F_{H}$/2).
Table 2. Results of the fit for each q2 range, together with several SM predictions. The inclusive $q^{2}$ = 1.00–22.00 $GeV^{2}$ range in the bottom line does not include events from the J/ψ and ψ(2S) resonance regions.
Forum