Vub| and B→η(′) form factors in covariant light-front approach

• Published in: Physics letters. B Vol. 686; no. 2-3; pp. 118 - 123
• Main Authors: Chen, Chuan-Hung, Shen, Yue-Long, Wang, Wei
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier B.V 22.03.2010; Elsevier
• Subjects: B-meson; Exact sciences and technology; Heavy quark; Nuclear physics; Physics; QCD; The physics of elementary particles and fields; Heavy quark; B-meson; QCD; Branching ratio; Uncertainty; Asymmetry; Leptons; Covariant theory; Form factors
• ISSN: 0370-2693; 1873-2445
• DOI: 10.1016/j.physletb.2010.02.056

B→(π,η,η′) transition form factors are investigated in the covariant light-front approach. With theoretical uncertainties, we find that B→(π,η,η′) form factors at q2=0 are f+(π,η,η′)(0)=(0.245−0.001+0.000±0.011,0.220±0.009±0.009,0.180±0.008−0.007+0.008) for vector current and fT(π,η,η′)(0)=(0.239−0.003−0.018+0.002+0.020,0.211±0.009−0.015+0.017,0.173±0.007−0.013+0.014) for tensor current, respectively. With the obtained q2-dependent f+π(q2) and observed branching ratio (BR) for B¯d→π+ℓν¯ℓ, the Vub is found as |Vub|LF=(3.99±0.13)×10−3. As a result, the predicted BRs for B¯→(η,η′)ℓν¯ℓ decays with ℓ=e,μ are given by (0.49−0.04−0.07+0.02+0.10,0.24−0.02−0.03+0.01+0.04)×10−4, while the BRs for D−→(η,η′)ℓν¯ℓ are (11.1−0.6−0.9+0.5+0.9,1.79−0.08−0.12+0.07+0.12)×10−4. In addition, we also study the integrated lepton angular asymmetries for B¯→(π,η,η′)τν¯τ: (0.277−0.001−0.007+0.001+0.005,0.290−0.000−0.003+0.002+0.003,0.312−0.000−0.006+0.004+0.005).