Related papers: Resummation of projectile-target multiple scatteri…
First-principles calculations of multi-hadron dynamics are a crucial goal in lattice QCD. Significant progress has been achieved in developing, implementing, and applying theoretical tools that connect finite-volume quantities to their…
I analyze the algebraic patterns underlying the structure of scattering amplitudes in quantum field theory. I focus on the decomposition of amplitudes in terms of independent functions and the systems of differential equations the latter…
As the study of three-hadron physics from lattice QCD matures, it is necessary to develop proper analysis tools in order to reliably study a variety of phenomena, including resonance spectroscopy and nuclear structure. Reconstructing the…
We derive an expression for the relation between two scattering transition amplitudes which reflect the same dynamics, but which differ in the description of their initial and final state vectors. In one version, the incident and scattered…
I review the recent progress in the evaluation of two-loop massive QCD amplitudes necessary for the description of hadronic scattering processes at the LHC. I put a special emphasis on the case of top-quark final states.
The scattering theory of the integrable statistical models can be generalized to the case of systems with extended lines of defect. This is done by adding the reflection and transmission amplitudes for the interactions with the line of…
A new effective action for the high energy quark-quark scatterings is obtained by applying a scaling approximation to the QCD action. The propagators are shown to factorize into the transverse and the longitudinal parts so that the…
We present a new method of resummation of QCD threshold distributions to the hard scattering function of the dilepton production cross section in hadron-hadron collisions. Our formulation by-passes the infrared singularities of the QCD…
We study two-to-two scattering amplitudes of a scalar particle of mass $m$. For simplicity, we assume the presence of $\mathbb{Z}_2$ symmetry and that the particle is $\mathbb{Z}_2$ odd. We consider two classes of amplitudes: the fully…
We propose stringy hadronic amplitudes that combine some of the features of sister trajectories and running tension. By summing over string amplitudes with varying Regge trajectories that have integer tension and converging intercept, we…
In this paper, the interaction of an incident finite amplitude longitudinal wave with a localized region of nonlinearity is considered. This interaction produces a secondary field represented by a superposition of first-, second-, and…
The analyticity properties of the scattering amplitude in the nonforward direction are investigated for a field theory in the manifold $\mathbb{R}^{3,1}\times S^1$. A scalar field theory of mass $m_0$ is considered in $D = 5$ Minkowski…
In this talk, we present the first chiral extrapolation of a resonant scattering amplitude obtained from lattice QCD. Finite-volume spectra, determined by the Hadron Spectrum Collaboration at $m_\pi = 236$ MeV, for the isotriplet $\pi\pi$…
It is shown that amplitude-based, exact resummation tames the un-cancelled IR divergences at O(alpha_s^2) in initial state radiation in QCD with massive quarks. Implications for precision predictions for LHC physics are discussed.
Modeling multipacting to steady state saturation is of interest in determining the performance of micro-pulse electron gun. In this paper, a novel method is proposed to calculate the multipacting resonance parameters for the gun. This…
We present an expression for the QCD amplitude for a general hard scattering process with any number of soft gluon emissions, to one-loop accuracy. The amplitude is written in two different but equivalent ways: as a product of operators…
We present a new method for computing multi-loop scattering amplitudes in Quantum Field Theory. It extends the Generalized Unitarity method by constraining not only the integrand of the amplitude but also its full integrated form. Our…
The exact analytical solutions of the Schr\"odinger equation for the generalized symmetrical Woods-Saxon potential are examined for the scattering, bound and quasi-bound states in one dimension. The reflection and transmission coefficients…
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,…
In this paper, we present an improvement of a method for computing scattering amplitudes that include external (polarized) fermions with the following features: the formulas are quite general and work for different kinematic configurations…