Related papers: Refactorisation in subleading $\bar B \to X_s \gam…
Using methods of effective field theory, factorized expressions for arbitrary B -> X_u l nu decay distributions in the shape-function region of large hadronic energy and moderate hadronic invariant mass are derived. Large logarithms are…
In this thesis we present an introduction to Soft-Collinear Effective Theory, which can be used to prove (or disprove) factorization theorems to all orders in the strong coupling constant for some B decays into light and energetic…
We investigate sum rules for heavy-to-light transition form factors at large recoil derived from correlation functions with interpolating currents for light pseudoscalar or vector fields in soft-collinear effective theory (SCET). We…
We present the first analytic ${\cal O}(\alpha_s)$-computation at twist-$1$,$2$ of the $\bar B_{u,d,s} \to \gamma$ form factors within the framework of sum rules on the light-cone. These form factors describe the charged decay $\bar B_u \to…
I discuss the two-particle subleading power corrections in radiative leptonic $B \to \gamma \ell \nu$ decay at next-to-leading order in $\alpha_s$ with the dispersion approach. Employing the method of regions, factorization of the $B \to…
Extraction of the mass difference $\Delta m$ from $B^0\bar B^0$ oscillations involves tagging of bottom flavour at production and at decay. We show that the asymmetry between the unmixed and mixed events factorizes into two parts, one…
We apply Soft-Collinear Effective Theory to prove at leading power in Lambda_QCD/m_b a factorization formula for the radiative leptonic decay B -> gamma l nu. Large logarithms entering the hard-scattering kernel are systematically resummed…
Heavy quark production in $\gamma\gamma$ collisions is reanalyzed. It is argued that evaluating the cross section $\sigma(\gamma\gamma\to Q\overline{Q})$ in a well-defined renormalization scheme requires the inclusion of direct photon…
Using the formalism of soft-collinear effective theory, a complete separation of short- and long-distance contributions to heavy-to-light transition form factors at large recoil is performed. The universal functions $\zeta_M(E)$…
After a brief introduction to the problem of subtraction of infrared divergences for high-order collider observables, we present a preliminary study of strongly-ordered soft and collinear multiple radiation from the point of view of…
We present a concise review of the recent theoretical progress concerning the standard model calculation of the inclusive radiative Bbar -> X_s gamma decay. Particular attention is thereby devoted to the calculations of the…
We derive and solve the renormalisation-group (RG) equation of the shape function $g_{17}(\omega,\omega_1;\mu)$, which appears at subleading power in the factorization of the inclusive decays $\bar{B} \to X_s \gamma$ and $\bar B \to X_s…
We considered the power corrections to the amplitude describing hard exclusive pion pair production in gamma gamma collisions at large energy and momentum transfer. In order to derive a factorization formula for the subleading power…
The charged-Higgs contributions to the decay \bar{B} -> X_s gamma are discussed in the minimal supersymmetric standard model at large tan beta. These contributions receive two-loop O(alpha_s tan beta) corrections by squark-gluino subloops,…
The contribution of subleading jet functions to inclusive decay distributions of $B$ mesons are derived from a systematic two-step matching of QCD current correlators onto soft collinear and heavy quark effective theory. Focusing on the…
The $B$-meson light-cone distribution amplitude is an important non-perturbative quantity arising in the factorization of the amplitudes for many exclusive decays of $B$ mesons, such as $B^-\to\gamma\,\ell^-\bar\nu$. We reconsider the…
The form factors of $B\to\pi(\rho)$ decays are analyzed using the light-cone sum rules in the framework of the soft-collinear effective theory (SCET). We establish the sum rules for the leading and the next-to-leading order (NLO)…
We show that the factorization assumption in color-suppressed $B$ meson decays is not ruled out by experimental data on $B \ra K(K^*) + J/\Psi(\Psi^{'})$. The problem previously pointed out might be due to an inadequate choice of hadronic…
We study quantitatively the importance of the recently derived NLO corrections to the DIS structure functions at small x in the dipole formalism. We show that these corrections can be significant and depend on the factorization scheme used…
We summerize the status of factorization hypothesis in the color-suppressed B meson decays : $B \to J/\psi K^{(*)}$. We present the general formalism for decay rates and polarization fractions with considering all possible non-factorizable…