Related papers: The $B_K$ Kaon Parameter in the Chiral Limit
We calculate the next-to-leading corrections to the branching ratio of exclusive $B\to K^* \gamma$ decay. The renormalization scale dependence is reduced compared to the leading logarithmic result but there remains a dependence on a cutoff…
In this short review, I present the recent lattice computations of kaon weak matrix elements relevant to $K \to \pi\pi$ decays and neutral kaon mixing. These matrix elements are key to the theoretical determination of the CP violation…
We present a determination, from lattice QCD, of charge symmetry violation in the spin- independent and spin-dependent parton distribution functions of the nucleon. This is done by chirally extrapolating recent QCDSF/UKQCD Collaboration…
It is shown that the principal pattern in baryon spectroscopy, which is associated with the flavor-spin dependent hyperfine interaction, is due to the spontaneous breaking of chiral symmetry in QCD and persists in the chiral limit. All…
We calculate the pion and kaon electromagnetic form factors in finite volume for a generic momentum transfer in space-like region, using SU(3) chiral perturbation theory. To this end, we first find the hadronic matrix element in a new form…
In this paper, we calculate the next-to-leading order (NLO) quantum chromodynamics (QCD) corrections to the exclusive processes $B_c^+\to \chi_{cJ}(h_c)\pi^+$ in the framework of the nonrelativistic QCD (NRQCD) factorization formalism. The…
A new method for computing hadronic effects on electroweak radiative corrections to low-energy weak interaction semileptonic processes is described. It employs high order perturbative QCD results originally derived for the Bjorken sum rule…
Many theories, from Supersymmetry to models of Strong Electroweak Symmetry Breaking, look at the production of four top quarks as an interesting channel to evidentiate signals of new physics beyond the Standard Model. The production of…
Semileptonic decay of the $B_c$ meson is studied in the heavy quark limit. The six possible form factors for $B_c \rightarrow B_s (B^0),B_s^* (B^{*0})$ semileptonic decay are determined by two invariant functions. Only one of these…
We present precision corrections to dispersion relation bounds on form factors in bottom hadron semileptonic decays and analyze their effects on parameterizations derived from these bounds. We incorporate QCD two-loop and nonperturbative…
The $B^* B\pi$ coupling is a fundamental parameter of chiral effective Lagrangian with heavy-light mesons and can constrain the chiral behavior of $f_B$, $B_B$ and the $B\to \pi l \nu$ form factor in the soft pion limit. We compute the $B^*…
In this paper we investigate the high-energy behavior of two-point and three-point Green functions of the QCD chiral currents and densities using the framework of the operator product expansion in the chiral limit. In detail, we study the…
I give a brief introduction to the scope of lattice QCD calculations in our effort to extract the fundamental parameters of the standard model. This goal is illustrated by two examples. First I discuss the extraction of CKM matrix elements…
We describe the calculation of the $B\rightarrow \pi$ hadronic matrix element from operator product expansion near the light-cone in QCD. In the resulting sum rules, the form factors $f^+$ and $F_0$ determining this matrix element are…
We summarize some of the difficulties that confront lattice calculations of non-leptonic kaon decay matrix elements. We review some of the methods that have been proposed to overcome these difficulties, and discuss the importance of…
We update the constraints on the right-handed $W_R$ gauge boson mass, mixing angle $\zeta$ with the left-handed $W_L$ gauge boson, and other parameters in general left-right symmetric models with different mechanisms of CP violation.…
The CKM matrix element $|V_{us}|$ can be extracted from the experimental measurement of semileptonic $K\to\pi$ decays. The determination depends on theory input for the corresponding vector form factor in QCD. We present a preliminary…
Baryon magnetic moments are computed in baryon chiral perturbation theory in the large-$N_c$ limit at one-loop order, where $N_c$ is the number of color charges. Orders $\mathcal{O}(m_q^{1/2})$ and $\mathcal{O}(m_q \ln m_q)$ corrections are…
This PhD thesis is a first step towards the control of the quantum corrections in the Resonance Chiral Theory, the suggested framework to handle QCD in the resonance region. After a theoretical introduction, Chapter 3 is devoted to…
The electromagnetic properties of baryons containing a heavy quark are calculated at next-to-leading order in partially quenched heavy hadron chiral perturbation theory. Calculations are performed for three light flavors in the isospin…