Semileptonic meson decays in point-form relativistic quantum mechanics: unambiguous extraction of weak form factors

Abstract

The point-form version of the Bakamjian-Thomas construction is applied to the description of several semileptonic decays of mesons. Weak form factors are extracted without ambiguity for pseudoscalar-to-pseudoscalar as well as for pseudoscalar-to-vector transitions of mesons from the most general covariant decomposition of the weak current. No manifestation of cluster-separability violation appears in the form of non-physical contributions to the structure of such a current, in contrast to what happens in the electromagnetic case. Moreover, no frame dependence is observed when we extract the form factors from the most general covariant decomposition of the current, which contrasts with analogous front-form calculations that involve vector mesons in the transition. We present our results for heavy-light meson decays, i.e. $B\to D$, as well as for $B$ and $D$ mesons decaying into $\pi$, $\rho$ and $K^{(\ast )}$ and perform a numerical comparison with the analogous front-form approach. Differences between point and front forms that are not seen in the heavy-quark limit of $q\bar{Q}$-systems appear. These differences are attributed to the different role that the non-valence contributions play in the description of hadronic reactions in each form. It is argued how contributions from missing $Z$-graphs can be estimated.

arXiv comment14 pages, 13 figures, 7 tables, accepted for publication in Physical Review D

References in corpus (25)

• Heavy Quark Symmetry
• Explicitly Covariant Light-Front Dynamics and Relativistic Few-Body Systems
• Mesonic Form Factors and the Isgur-Wise Function on the Light-Front
• Consistent treatment of spin-1 mesons in the light-front formalism
• Space-like and time-like pion electromagnetic form factor and Fock state components within the Light-Front dynamics
• Transition Form Factors between Pseudoscalar and Vector Mesons in Light-Front Dynamics
• Electromagnetic rho-meson form factors in point-form relativistic quantum mechanics
• Vector mesons in a relativistic point-form approach
• Constructing Point Form Mass Operators from Interaction Lagrangians
• Comparison among Hamiltonian light-front formalisms at q+ = 0 and q+ <> 0: space-like elastic form factors of pseudoscalar and vector mesons
• Point-Form Hamiltonian Dynamics and Applications
• Electromagnetic meson form factor from a relativistic coupled-channel approach
• Electroweak form factors of heavy-light mesons -- a relativistic point-form approach
• Light-front zero-mode contribution to the tensor form factors for the exclusive rare $P\to V{\ell }^{+}{\ell }^{-}$ decays
• Light-front dynamic analysis of transition form factors in the process of $P\to V\ell {\nu }_{\ell }$
• The nucleon wave function in light-front dynamics
• Boost operators in Coulomb-gauge QCD: the pion form factor and Fock expansions in phi radiative decays
• Comment on the equivalence of Bakamjian-Thomas mass operators in different forms of dynamics
• Model tests of cluster separability in relativistic quantum mechanics
• Axial-vector mesons in a relativistic point-form approach
• Form Factors of Few-Body Systems: Point Form Versus Front Form
• Hadron structure within the point form of relativistic quantum mechanics
• Form factors of heavy-light systems in point-form relativistic quantum mechanics: the Isgur-Wise function
• Angular momentum decomposition of chiral multiplets in front form
• Light-Front Model of Transition Form-Factors in Heavy Meson Decay

Cited by in corpus (3)

• Effects of a dressed quark-gluon vertex in vector heavy-light mesons and theory average of B(c)* meson mass
• Aspects of open-flavour mesons in a comprehensive DSBSE study
• Weak transition form factors of heavy-light pseudoscalar mesons for space- and timelike momentum transfers