Related papers: Light Flavor Dependence of the Isgur-Wise Function
The leading Isgur-Wise form factor $\xi(y)$ parametrizing the semileptonic transitions $\Lambda_b\to\Lambda^{1/2}_{c1}\ell\bar\nu$ and $\Lambda_b\to\Lambda^{3/2}_{c1}\ell\bar\nu$ is calculated by using the QCD sum rules in the framework of…
We determine chiral loop corrections to the B meson decay amplitudes to positive and negative parity charmed mesons within a framework which combines heavy quark and chiral symmetries. Then we investigate the impact of the lowest-lying…
The light Higgs boson of the Standard Model could arise as the consequence of the weakly broken conformal symmetry in a strongly interacting gauge theory. Here we present a novel idea to study the transition from conformal to confining…
We calculate the B-meson decay constants f_B, f_Bs, and their ratio in unquenched lattice QCD using domain-wall light quarks and relativistic b-quarks. We use gauge-field ensembles generated by the RBC and UKQCD collaborations using the…
We calculate the leptonic decay constants of heavy-light pseudoscalar mesons with charm and bottom quarks in lattice quantum chromodynamics on four-flavor QCD gauge-field configurations with dynamical $u$, $d$, $s$, and $c$ quarks. We…
QCD sum rules are used to estimate the flavour SU(3)-symmetry violation in two-body B decays to pions and kaons. In the factorizable amplitudes the SU(3)-violation manifests itself in the ratio of the decay constants f_K/f_pi and in the…
In this work we investigate the weak $\Lambda_{b}\to\Lambda_c$ semi-leptonic and non-leptonic decays. The light-front quark model and diquark picture for heavy baryons are adopted to evaluate the $\Lambda_{b}\to\Lambda_c$ transition form…
Fragmentation functions for charged particles in Z -> qq(bar) events have been measured for bottom (b), charm (c) and light (uds) quarks as well as for all flavours together. The results are based on data recorded between 1990 and 1995…
We study the direct CP asymmetry in B -> X_s gamma decay in SUSY models with non-universal A-terms. We show that the flavour-dependent phases of the A-terms, unlike the flavour-independent ones, can give rise too large contribution to the…
Sum rules based upon heavy quark effective theory indicate that the Isgur-Wise function $\xi(w)$ has a minimum slope as w approaches 1, which is zero for light degrees of freedom with zero spin and 1/4 for light spin 1/2. Quark-model…
We review our method and numerical results for calculation of the Isgur-Wise function on the lattice. We present a discussion of the systematic errors. Using recent experimental results, we find $V_{cb} = 0.044\pm 0.005\pm .007$.…
Exclusive semileptonic B decays to orbitally and radially excited charmed mesons are investigated in the first order of the heavy quark expansion. The emerging leading and subleading Isgur-Wise functions are calculated in the framework of…
In the framework of the instantaneous Bethe Salpeter equation we investigate weak decays of B and D mesons. Mesons are described as q-bar q states interacting via a mixture of a scalar and a vector confining kernel and a one gluon exchange.…
We calculate the $\Lambda_b \to \Lambda_c \ell \nu$ form factors and decay rates for all possible $b\to c \ell\bar\nu$ four-Fermi interactions beyond the Standard Model, including nonzero charged lepton masses and terms up to order…
Precise measurements of the top quark decay properties at hadron colliders offer interesting new possibilities of testing the standard model. At the same time, recent intriguing experimental results concerning CP violation in the B_d and…
Recent experimental and theoretical progress regarding B --> K(*) l+ l- decays led to improved bounds on the Wilson coefficients C_9 and C_10 of four-fermion operators of the |Delta B|=|Delta S|=1 effective Hamiltonian. We analyze the…
We calculate the vector and axial-vector form factors of $B_{u,d,s}$ decays into P-wave axial-vector mesons in the light-cone sum rule approach. For the sum rule results, we have included corrections of order $m_A/m_b$, where $m_A$ is the…
We present the current status of the MILC collaboration's calculations of the properties of the light pseudoscalar meson sector. We use asqtad staggered ensembles with 2+1 dynamical flavors down to $a \approx 0.045$ fm and light quark mass…
The decays of top quark $t\rightarrow c\gamma,\;t\rightarrow cg,\;t\rightarrow cZ,\;t\rightarrow ch$ are extremely rare processes in the standard model (SM). The predictions on the corresponding branching ratios in the SM are too small to…
I present one-loop level calculations of the Isgur-Wise functions for B -> D^{(*)} + e + nu, of the matrix elements of isovector twist-2 operators in B and D mesons, and the matrix elements for the radiative decays D^* -> D + gamma in…