Ward identities, B → V transition form factors and applications

37th Brazilian Meeting on Nuclear Physics

Paracha, M. Ali^1,2 ; El-Bennich, Bruno^1,3 ; Aslam, M. Jamil^4 ; Ahmed, Ishtiaq^1,5

Laboratório de Física Teórica e Computacional, Universidade Cruzeiro Do sul, São Paulo SP

01506-000, Brazil^1

Department of Physics, School of Natural Sciences, National University of Science and Technology, Islamabad, Pakistan^2

Instituto de Física Teórica, Universidade Estadual Paulista, São Paulo, SP

01140-070, Brazil^3

Department of Physics, Quaid-i-Azam University, Islamabad

45320, Pakistan^4

National Centre for Physics, Quaid-i-Azam University Campus, Islamabad

45320, Pakistan^5

关键词: Branching fractions;    Branching ratio;    Distance effects;    Effective Hamiltonian;    Form factors;    Transition amplitudes;    Vector meson;    Ward identities;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/630/1/012050/pdf
DOI  :  10.1088/1742-6596/630/1/012050

来源: IOP

【 摘 要 】

Long distance effects are studied in the rare exclusive semileptonic B(d,s) → V+-decays, where V denotes a K∗ or φ meson. The form factors, which describe the meson transition amplitudes in the effective Hamiltonian approach, are calculated by means of Ward identities, experimental constraints and extrapolated within a general vector meson dominance framework. These form factors are then compared to the ones obtained in Lattice QCD simulations, with Light Cone Sum Rules and a Dyson-Schwinger equation approach. Additionally, the Bd→ K∗+-and Bs→ φ+-branching ratios are computed and the differential branching fractions are given as a function of the squared-momentum transfer.