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Abstract Particle physics is the study of the particles that make up the universe, and the interactions that take place between them. It is also referred to as elementary particle physics, by which we mean that we would ideally like to understand the universe in terms of its “elementary” constituents that are not composed of other particles. Why do we study particle physics? The questions “What is the universe made of?”and “How does it work?” are of fundamental interest for their own sake. In addition, understanding the universe as it is now might help us answer the question “where did it come from?” Aside from these weighty questions, what about immediate material benefits? Like much of fundamental research, it is impossible to know now what benefits might be realized from particle physics. However, it is worth noting that in 1897 the quest to understand the universe led to the discovery of the electron by J.J. ThompsonThe Standard Model provides a unified framework for our current understanding of fundamental forces and particles. The fundamental particles include leptons, quarks and gauge bosons. Leptons include electrons and their heavier cousins the muons and taus as well as associated neutrinos. Interactions between the fundamental particles are seen as arising from the exchange of gauge bosons: photons for electromagnetic, W and Z bosons for weak and gluons for strong interactions. The Standard Model also predicts the existence of the Higgs boson, which couples with many of the other fundamental particles to give them mass [1]. The elementary particles included in the Standard Model are shown in Figure (1.1The Standard Model recognizes two types of elementary fermions: quarks and leptons. In all, the model distinguishes 24 different fermions: six quarks: the up quark, down quark, strange quark, charmed quark, bottom quark, and top quark; and six leptons (electron, electron neutrino, muon, muon neutrino, tau particle, tau neutrino), each with a corresponding anti particle. The 12 fundamental fermionic flavours are divided into three generations of four particles each. Six of the particles are quarks. The remaining six are leptons, three of which are neutrinos, and the remaining three of which have an electric charge of −1: the electron and its two cousins, the muon and the tau. There are also 12 fundamental fermionic antiparticles that correspond to these 12 particles. For example, the anti electron (positron) e+ is the electron’s antiparticle and has an electric charge of +1.Table (1.1) shows the 12 fundamental fermionic flavours and fundamental fermionic antiparticles are listed in Table (2.2) [2].Particles obey the Bose-Einstein statistics are called bosons, In the Standard Model, vector (spin-1) bosons (gluons, photons, and the W and Z bosons) mediate forces, whereas the Higgs boson (spin-0) is responsible for the intrinsic mass of particles. Bosons differ from fermions in the fact that multiple bosons can occupy the same quantum state (Pauli Exclusion Principle). Also, Bosons can be either elementary, like photons, or a combination, like mesons. The spin of bosons is integers instead of half integers. There are only five particles that considered as elementary particles [3]. |