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Classification of elementary particles.

Classification of elementary particles.

On the basis of spin property, elementary particles are classified into two types namely;
Bosons
Fermions
Bosons
Bosons are the particles having integral spin and follows Bose Einstein Statistics. Bosons are further classified into two types namely massless bosons and mesons.
Massless bosons
Massless bosons include photons and gravitons.
Photons 
Photons are quantum of electromagnetic radiation. They are massless and chargeless particle and have spin 1. 
Gravitons
Gravitons are supposed to be responsible for the gravitational field. No gravitons are detected experimentally so far. Gravitons are massless, chargeless particles having spin 2.
    Both photons and gravitons are consider to be antiparticles of themselves.
Mesons
Mesons are strongly interacting zero spin particle. Mesons owe their existence to cosmic rays. The members of this group are π mesons, η mesons and k mesons.
π mesons
π mesons are also called pions. π mesons are of three types π⁺, π⁻ and π⁰ mesons. The antiparticle of π⁰ is itself. π⁻ is the antiparticle of π⁺.
k mesons
k mesons are also called kaons. K mesons are of four types.
Types of k mesons.
Types of k mesons.

η mesons
η mesons are neutral particle. η⁰ is the antiparticle of itself.
Fermions
Fermions are the particles having half integral spin and follows Fermi Dirac Statistics. Fermions are further classified into two types namely leptons and baryons.
Leptons
Leptons are light particle having spin 1/2. The member of this group are electrons and positrons, positive and negative muons and neutrino and antineutrino.
Electrons and positrons
Electrons are negatively charged, stable atomic particles. The positrons are similar to electrons in all respect except that it is positively charge. Positrons are antiparticle of electrons.
Muons
The positive and negative 𝜇 particles ( 𝜇⁺,  𝜇⁻) are called muons. Muon is an unstable particle and soon decays.
Neutrino and antineutrino
These particles have negligible rest mass and zero charge. 
Baryons
Baryons are the particles having rest mass equal to or greater than that of nucleons. Baryons are fermions with half integral spin i.e 1/2, 3/2 etc. Baryons include nucleons and hyperons. Baryons and mesons are together called hadrons.
Nucleons
Nucleons include protons, neutrons and their antiparticle antiprotons and antineutrons. Both protons and neutrons have spin 1/2.
Hyperons
These are the particles having rest mass greater than that of nucleons. Hyperons include lambda particle Λ⁰, sigma particle (Σ), cascade particle (𝜩) and omega particle (𝛀). All these particles have spin 1/2 except 𝛀 particle which have spin 3/2.
Classification of elementary particles.
Classification of elementary particles.

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