Study of the leptonic decays of pseudoscalar B,D and vector B*,D* mesons and of the semileptonic B{yields}D and B{yields}D* decays

Journal Article · Wed Jun 01 04:00:00 EDT 2005 · Physical Review. D, Particles Fields

DOI:https://doi.org/10.1103/PhysRevD.71.113006· OSTI ID:20709437

Albertus, C; Nieves, J ^[1]; Hernandez, E; Verde-Velasco, J M ^[2]

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1. Departamento de Fisica Moderna, Universidad de Granada, E-18071 Granada (Spain)
2. Grupo de Fisica Nuclear, Facultad de Ciencias, E-37008 Salamanca (Spain)

We present results for different observables in weak decays of pseudoscalar and vector mesons with a heavy c or b quark. The calculations are done in a nonrelativistic constituent quark model improved at some instances by heavy quark effective theory constraints. We determine pseudoscalar and vector meson decay constants that within a few percent satisfy f{sub V}M{sub V}/f{sub P}M{sub P}=1, a result expected in heavy quark symmetry when the heavy quark masses tend to infinity. We also analyze the semileptonic B{yields}D and B{yields}D* decays for which we evaluate the different form factors. Here we impose heavy quark effective theory constraints among form factors that are not satisfied by a direct quark model calculation. The value of the form factors at zero recoil allows us to determine, by comparison with experimental data, the value of the |V{sub cb}| Cabibbo-Kobayashi-Maskawa matrix element. From the B{yields}D semileptonic decay we get |V{sub cb}|=0.040{+-}0.006, in perfect agreement with our previous determination based on the study of the semileptonic {lambda}{sub b}{yields}{lambda}{sub c} decay and also in excellent agreement with a recent experimental determination by the DELPHI Collaboration. We further make use of the partial conservation of axial current hypothesis to determine the strong coupling constants g{sub B*B{pi}}(0)=60.5{+-}1.1 and g{sub D*D{pi}}(0)=22.1{+-}0.4. The ratio R=(g{sub B*B{pi}}(0)f{sub B*}{radical}(M{sub D}))/(g{sub D*D{pi}}(0)f{sub D*}{radical}(M{sub B}))=1.105{+-}0.005 agrees with the heavy quark symmetry prediction of 1.

• OSTI ID: 20709437
• Journal Information: Physical Review. D, Particles Fields, Journal Name: Physical Review. D, Particles Fields Journal Issue: 11 Vol. 71; ISSN PRVDAQ; ISSN 0556-2821
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
B MESONS
B QUARKS
C QUARKS
COMPARATIVE EVALUATIONS
COUPLING CONSTANTS
D MESONS
D*-2010 MESONS
FORM FACTORS
KOBAYASHI-MASKAWA MATRIX
LAMBDA BARYONS
LEPTONIC DECAY
QUARK MODEL
SEMILEPTONIC DECAY
STRONG-COUPLING MODEL
SYMMETRY
T QUARKS