الفهرس 
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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].