s → K semileptonic decay from an Omnès improved nonrelativistic quark model

11th International Conference on Hyperons, Charm and Beauty Hadrons

Hernández, E.^1 ; Albertus, C.^2 ; Hidalgo-Duque, C.^3 ; Nieves, J.^3

Departamento de Física Fundamental e IUFFyM, Universidad de Salamanca, Plaza de la Merced s/n, Salamanca

E-37008, Spain^1

Departamento de Física Atómica, Nuclear y Molecular, Instituto Carlos I de Física Teórica y Computacional, Universidad de Granada, Avenida de Fuentenueva s/n, Granada

E-18071, Spain^2

Instituto de Física Corpuscular (IFIC), Centro Mixto CSIC-Universidad de Valencia, Institutos de Investigación de Paterna, Apartado 22085, Valencia

E-46071, Spain^3

关键词: Dispersion relations;    Form factors;    Lattice QCD;    Nonrelativistic;    Quark model;    Semileptonic decay;    Sum rule;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/556/1/012026/pdf
DOI  :  10.1088/1742-6596/556/1/012026

来源: IOP

【 摘 要 】

We study the f+form factor for the B¯s→ K+-ν¯semileptonic decay in a nonrelativistic quark model. The valence quark contribution is supplemented with a B¯∗-pole term that dominates the high q2region. To extend the quark model predictions from its region of applicability near q2max(MBs-MK)2we use a multiply-subtracted Omnès dispersion relation. We fit the subtraction constants to a combined input from previous light cone sum rule results in the low q2region and the quark model results (valence plus B¯∗-pole) in the high q2region. From this analysis, we obtain Γ(B¯s→ K+-ν¯) (5.47+5.54-0.46)|Vub|2× 10-9MeV, which is about 10% and 20% higher than predictions based on Lattice QCD and QCD light cone sum rules respectively.