Related papers: Multi-Parton Scattering Amplitudes via On-Shell Me…
We show that the evaluation of scattering amplitudes can be formulated as a problem of multivariate polynomial division, with the components of the integration-momenta as indeterminates. We present a recurrence relation which, independently…
We discuss the structure of infrared and ultraviolet singularities in on-shell QCD and supersymmetric QCD amplitudes at one-loop order. Previous results, valid for massless partons, are extended to the case of massive partons. Using…
We describe two independent methods to calculate the angular distribution of muons after traversing a thick scatterer due to multiple Coulomb scattering. Both methods take into account the nuclear size effect. We demonstrate a necessity to…
A new method for the determination of the real part of the elastic scattering amplitude is examined for high energy proton-proton elastic scattering at small momentum transfer. This method allows us to decrease the number of model…
We examine present data for double parton scattering at LHC and discuss their energy dependence from its earliest measurements at the ISR. Different models for the effective cross-section are considered and their behavior studied for a…
Meson-Baryon Interactions can be successfully described using both Chiral Symmetry and Unitarity. The $s-$wave meson-baryon scattering amplitude is analyzed in a Bethe-Salpeter coupled channel formalism incorporating Chiral Symmetry in the…
We discuss results from a recently proposed all-order description of hard, radiative corrections to certain multi-jet processes at hadron colliders. The description is based on obtaining an all-order estimate of the t-channel singularities…
We review recent developments in the calculation of QCD loop amplitudes with several external legs, and their application to next-to-leading order jet production cross-sections. When a number of calculational tools are combined together ---…
Polarized Compton scattering on the deuteron is studied in nuclear effective field theory. A set of tensor structures is introduced to define 12 independent Compton amplitudes. The scalar and vector amplitudes are calculated up to ${\cal…
Within the framework of potential scattering theory we derive an analytical two-potential formula for the on-shell partial wave scattering amplitude. This formula embodies a large number of possible applications, including long range…
We first propose a general method to construct the complete set of on-shell operator bases involving massive particles with any spins. To incorporate the non-abelian little groups of massive particles, the on-shell scattering amplitude…
A fascinating new generation of experiments has determined certain meson scattering parameters at high precision. A confluence of highly sophisticated theory as well as new experimental ideas have led to this state of affairs, which sheds…
In this paper we found the nucleus-nucleus scattering amplitude at high energies by summing large Pomeron loops. It turns out that the energy dependence of this amplitude is the same for dipole-dipole scattering. This happens since the…
The double parton collisions become increasingly important at high energies. The scale factors are the dimensional parameters which characterize these interactions and are the physical observables that can provide a first quantitative…
Recent work on leading order multiparton calculations for hadronic collisions is reviewed, with special emphasis on the ALPGEN event generator. Some problems connected with the interface of the partonic events generated via matrix elements…
The multidimensional space-time with $(D-4)$ compact extra space dimensions and SM fields confined on four-dimensional brane is considered. The elastic scattering amplitude of two particles interacting by gravitational forces is calculated…
We illustrate the use of new on-shell methods, 4-dimensional unitarity cuts combined with on-shell recursions relations, by computing the A_4^{(1)}(phi,1^-,2^-,3^+,4^+) amplitude in the large top mass limit where the Higgs boson couples to…
The recently developed on-shell bootstrap for computing one-loop amplitudes in non-supersymmetric theories such as QCD combines the unitarity method with loop-level on-shell recursion. For generic helicity configurations, the recursion…
Coupled-channel dynamics for scattering and production processes in partial-wave amplitudes is discussed from a perspective that emphasizes unitarity and analyticity. We elaborate on several methods that have driven to important results in…
We report on our one-loop calculation of all the two meson scattering amplitudes within SU(3) Chiral Perturbation Theory, i.e. with pions, kaons and etas. Once the amplitudes are unitarized with the coupled channel Inverse Amplitude Method,…