Semileptonic charmed BB meson decays in Universal Extra Dimension Model

Form factors parameterizing the semileptonic decay $B_{c}\rightarrow D_{s}^{\ast}l^{+}l^{-}$ ($l=\mu ,\tau$) are calculated using the frame work of Ward Identities. These form factors are then used to calculate the physical observables like branching ratio and helicity fractions of final state $D_{s}^{\ast}$ meson in these decay modes. The analysis is then extended to the the universal extra dimension (UED) model where the dependence of above mentioned physical variables to the compactification radius R, the only unknown parameter in UED model, is studied. It is shown that the helicity fractions of $D_{s}^{\ast}$ are quite sensitive to the UED model especially when have muons as the final state lepton. Therefore, these can serve as a useful tool to establish new physics predicted by the UED model.Comment: 17 pages, 4 figure

Semileptonic charmed BB meson decays in Universal Extra Dimension Model

Form factors parameterizing the semileptonic decay $B_{c}\rightarrow D_{s}^{\ast}l^{+}l^{-}$ ($l=\mu ,\tau$) are calculated using the frame work of Ward Identities. These form factors are then used to calculate the physical observables like branching ratio and helicity fractions of final state $D_{s}^{\ast}$ meson in these decay modes. The analysis is then extended to the the universal extra dimension (UED) model where the dependence of above mentioned physical variables to the compactification radius R, the only unknown parameter in UED model, is studied. It is shown that the helicity fractions of $D_{s}^{\ast}$ are quite sensitive to the UED model especially when have muons as the final state lepton. Therefore, these can serve as a useful tool to establish new physics predicted by the UED model.Comment: 17 pages, 4 figure

Insights into the quark-gluon vertex from lattice QCD and meson spectroscopy

By comparing successful quark-gluon vertex interaction models with the corresponding interaction extracted from lattice-QCD data on the quark's propagator, we identify common qualitative features which could be important to tune future interaction models beyond the rainbow ladder approximation. Clearly, a quantitative comparison is conceptually not simple, but qualitatively the results suggest that a realistic interaction should be relatively broad with a strong support at about $0.4-0.6$~GeV and infrared-finite