Radiative transitions in heavy mesons in a relativistic quark model

Abstract

The radiative decays of D*, B*, and other excited heavy mesons are analyzed in a relativistic quark model for the light degrees of freedom and in the limit of heavy quark spin-flavor symmetry. The analysis of strong decays carried out in the corresponding chiral quark model is used to calculate the strong decays and determine the branching ratios of the radiative D* decays. Consistency with the observed branching ratios requires the inclusion of the heavy quark component of the electromagnetic current and the introduction of an anomalous magnetic moment for the light quark. It is observed that not only D, but also B meson transitions within a heavy quark spin multiplet are affected by the presence of the heavy quark current.

Strong and radiative decays of heavy mesons in a covariant model

“…table 7. The results of LFQM [59] and the relativistic quark model (RQM) [60] are very close to ours. Finally, we list the predicted decay rates and branch ratios within this work and some theoretical models in table 8.…”

Measurement of the branching ratiosΓ(Ds*+→Ds+π0)/ΓAubert1, Barate2, Boutigny3 et al. 2005Phys. Rev. D16140View full textAdd to dashboardCite

“…Newer theoretical estimates in a relativistic quark model [2] predict B(D * + s → D + s π 0 ) ≈ 13%, somewhat larger than our measurement.…”

“…Ft,13.40.Hq,12.39.Fe The decay of any higher-mass cs meson into D + s π 0 [1] violates isospin conservation, thus guaranteeing a small partial width. The amount of suppression is a matter of large theoretical uncertainty according to most models of charm-meson radiative decay [2]. One such model [3] suggests that the decay D [4,5].…”

$$B^*_{s,d} \rightarrow \mu ^+ \mu ^-$$ B s , d ∗ → μ + μ - and its impact on $$B_{s,d} \rightarrow \mu ^+ \mu ^-$$ B s , d → μ + μ -

“…The predicted M1 widths are 0.15-400 eV and 10-300 eV for B * s → B s γ and B * d → B d γ , respectively [24,26,27,35,36]. Recently new predicted M1 widths were given in Ref.…”

“…We can estimate g B s B * s γ in several ways, including the heavy-quark and chiral effective theories [31,32] with the radiative and pion transition widths of D * + , the light cone QCD sum rules [33,34], and the radiative M1 decay widths of B * s → B s γ from the potential model [27,35]. The heavy-quark and chiral effective theories yield the following expression [13][14][15]:…”