Implications of Family Nonuniversal $Z^\prime$ Model on B -->K_0^* pi Decays

Abstract

Within the QCD factorization formalism, we study the possible impacts of the nonuniversal Z ′ model, which provides a flavor-changing neutral current at the tree level, on rare decays B → K * 0 π. Under two different scenarios (S1 and S2) for identifying the scalar meson K * 0 (1430), the branching ratios, CP asymmetries, and isospin asymmetries are calculated in both the standard model (SM) and the family nonuniversal Z ′ model. We find that the branching ratios and CP asymmetries are sensitive to weak annihilation. In the SM, with ρ A = 1 and φ A ∈ [−30 • , 30 • ], the branching ratios of S1 (S2) are smaller (larger) than the experimental data. Adding the contribution of the Z ′ boson in two different cases (Case-I and Case-II), for S1, the branching ratios are still far away from experiment. For S2, in Case-II, the branching ratios become smaller and can accommodate the data; in Case-I, although the center values are enhanced, they can also explain the data with large uncertainties. Similar conclusions are also reached for CP asymmetries. Our results indicate that S2 is more favored than S1, even after considering new physics effects. Moreover, if there exists a nonuniversal Z ′ boson, Case-II is preferred. All results can be tested in the LHC-b experiment and forthcoming super-B factory.

Revisiting charmless hadronic B decays to scalar mesons

“…The experimental measurements of B → SP and B → SV , where S, P, V stand for scalar, vector and pseudoscalar mesons, respectively, will provide valuable information on the nature of the even-parity mesons. On the theoretical side, hadronic B decays to scalar mesons have been studied in the QCD-inspired approaches: QCD factorization (QCDF) [6][7][8][9][10] and pQCD [11][12][13][14][15][16][17][18][19][20].…”

Charmless $B_s\to V S$ Decays in PQCD Approach

“…[3]. On the theoretical side, two-body B meson decays to scalar mesons have been explored widely in different approaches, such as the QCD factorization (QCDF) [4][5][6][25][26][27] and the perturbative QCD approach (PQCD) [28][29][30][31][32][33][34][35][36][37]. Combinations of the well measured experimental data with the precise theoretical predictions provide us another way to determine the nature of the scalar mesons.…”

Calculation of the $$B\rightarrow K_{0,2}^*(1430)f_0(980)/\sigma $$ decays in the perturbative QCD approach

“…So, in order to calculate these decays reliably, we should go beyond the naive factorization and evaluate the contributions from the nonfactorizable and annihilation type diagrams. In the past few years, the decays involving a scalar meson or a tensor meson in final states have been already explored in different approaches, such as the generalized factorization approach [28], QCD factorization (QCDF) [19,[29][30][31][32][33][34][35] and perturbative QCD approach (PQCD) [36][37][38][39][40][41][42][43][44][45][46][47][48][49][50][51][52][53][54]. Based on the researching achievements of processes, and stimulated by the experimental data, in this work ,we shall extend our studies to the B 0(+) → K * 0(+) 0 f 0 /σ and B 0(+) → K * 0(+) 2 f 0 /σ decays in PQCD approach, and try to provide new understanding to the mixing angle of the σ − f 0 mixing.…”