Tree level spinor helicity amplitude formalism for the standard model of electroweak and strong interactions

Abstract

In this thesis we study the spinor helicity formalism (SHF). This formalism is essentially based on Weyl spinors, where we write the physical quantities appearing in scattering amplitudes in terms of these spinors. Here we study two distinct cases: massless particles and massive ones and build the formalism for each case. After that, we apply SHF to study a few scattering processes including different sides of techniques necessary to acquire. We will also plot Feynman diagrams for scattering processes via the FeynArts package; illustrate how the amplitudes for these processes are obtained by using the FeynCalc package and showcase the SpinorsExtras package(sub-package of S@M) via a simple example to obtain the amplitudes in terms of spinor products. Key Words: Spinor Helicity Formalism, Tree Level Amplitude, Scattering Amplitude.