Related papers: Factorization at fixed Q^2(1-x)
Consistent factorization theorems in high-energy scattering near the threshold are presented in the framework of the soft-collinear effective theory. Traditional factorization theorem separates the soft and collinear parts successfully, but…
A method of deriving bounds on the weak meson form factors, based on perturbative QCD, analyticity and unitarity, is generalized in order to fully exploit heavy quark spin symmetry in the ground state $(L=0)$ doublet of pseudoscalar $(B)$…
We introduce a factorization formula for semi-leptonic $b \to u$ transitions in the exclusive decay mode $B^- \to \pi^+\pi^-\ell^-\bar\nu_\ell$ in the limit of large pion energies and large dipion invariant mass. One contribution can be…
In QCD the amplitude for B0 -> D(*)+pi- factorizes in the large Nc limit or in the large energy limit Q >> Lambda_QCD where Q = {m_b, m_c, m_b-m_c}. Data also suggests factorization in exclusive processes B-> D* pi+ pi- pi- pi0 and B-> D*…
We use multi-parton states to examine the leading order collinear factorization of single transverse-spin asymmetries in Drell-Yan processes. Twist-3 operators are involved in the factorization. We find that the so-called soft-gluon-pole…
In a framework for nonperturbative QCD calculation of high energy processes, the amplitudes for photo- and electroproduction of vector mesons are written as integrals of the overlap product of photon and vector meson wave functions,…
Single inclusive particle production cross sections in high energy hadron collisions at forward rapidity are an important benchmark process for the CGC picture of small x QCD. Recent calculations of this process have not led to a stable…
The formalism for uniform description of Drell-Yan transverse-momentum spectrum is presented in a framework of High-Energy Factorization, which smoothly interpolates between Collins-Soper-Sterman formalism at $|{\bf q}_T|\ll Q$ and usual…
We prove $k_T$ factorization theorem in perturbative QCD (PQCD) for exclusive processes by considering $\pi\gamma^*\to \gamma(\pi)$ and $B\to\gamma(\pi) l\bar\nu$. The relevant form factors are expressed as the convolution of hard…
Employing the QCD factorization formalism we compute $B_{u}^{-} \to \gamma^{\ast} \, \ell \, \bar \nu_{\ell}$ form factors with an off-shell photon state possessing the virtuality of order $m_b \, \Lambda_{\rm QCD}$ and $m_b^2$,…
We study the factorization of soft and collinear singularities in dimensionally-regularized fixed-angle scattering amplitudes in massless gauge theories. Our factorization is based on replacing the hard massless partons by light-like Wilson…
We reanalyze the factorization theorems for Drell-Yan process and for deep inelastic scattering near threshold, as constructed in the framework of the soft-collinear effective theory (SCET), from a new, consistent perspective. In order to…
Factorization underlies all predictions at the Large Hadron Collider, but has only been rigorously proven in a few cases. One of these cases is the Drell-Yan process, $pp \to Z/\gamma + X$, in the limit of small boson transverse momentum.…
We investigate the inclusive top quark pair production in proton-proton and proton-antiproton collisions at high energies in the framework of kt-factorization QCD approach. Our study is based on the off-shell partonic subprocesses g*g* ->…
Results on soft and hard diffraction in $pp$ and $\bar pp$ collisions are reviewed with emphasis on factorization and scaling properties of differential cross sections. While conventional factorization breaks down at high energies, a…
We discuss $1/Q$ corrections to hard processes in QCD where $Q$ is a large mass parameter like the total energy in $e^+e^-$ annihilation. The main problem we address ourselves to is whether these corrections to different processes…
We consider the factorization properties of on-shell QCD amplitudes with massive partons in the limit when all kinematical invariants are large compared to the parton mass and discuss the structure of their infrared singularities. The…
We find that in "two-photon"-like processes in the scalar $\varphi^3_E$ model and also in hadron-pair production arising from the collisions of a real (transversely polarized) and a highly virtual, longitudinally polarized, photon in QCD,…
QCD equations for the generating functions are applied to separate soft and hard jets in $e^+e^-$-processes of multiparticle production. The dependence of average multiplicities and higher moments of multiplicity distributions of particles…
The light-cone distribution amplitude (LCDA) of a heavy-light meson defined in heavy quark effective theory (HQET), is a fundamental nonperturbative input to account for innumerable $B$ meson exclusive decay and production processes. On the…