A lepton can be defined as an elementary particle that belongs to the sub-atomic class with half-integer spin (spin 1⁄2) that participates in electromagnetic or weak interactions. The word, Lepton comes from a Greek word that means small, fine, or thin. The most common example of leptons an electron. In this article, we look at the properties and types of leptons.
Classification of leptons based on charge
There are two main classes of Lepton: negatively charged Lepton and neutral leptons
Charged leptons (also known as the electron-like leptons)
Charged leptons can combine with other particles to form a composite particle. For example electron(charged lepton) combines with protons and neutrons to form an atom. Electrons are the lightest charged leptons.
Neutral leptons (better known as neutrinos)
Neutral leptons are generally non-reactive in nature.
Properties of Leptons
- Leptons respond to electromagnetic force, weak force, and gravitational force.
- Leptons can be neutral, or negatively charged.
- Charged leptons generate a magnetic field.
- The charge of the lepton determines the strength of their electric field and how they react to external electrical or magnetic fields.
- They do not interact with other strong forces.
Types of Leptons
It is found that there are six different types of Leptons-three negatively charged leptons and three neutral leptons. The electrically charged leptons are the electron, muon, and tauon. The electrically neutral leptons are called neutrinos. There are three different types of neutrinos: The electron neutrino, the muon neutrino, and the tauon neutrino
Electrons
Electrons are negatively charged particles. The electrons are connected with the chemical properties of almost all atoms. It is the smallest charged particle with decent stability.
Muons
Muons are particles where their mass is 207 times larger than electrons and is having a lifetime of 2.20 microseconds. They make up more than half of cosmic radiation at sea level. They are elementary particles similar to electrons with an electric charge of -1e. They are also unstable subatomic particles with a mean lifetime longer than other subatomic particles.
Tauons
They are the negatively charged elementary particles of mass 3477.48×electron mass classed as Lepton. They are weak isospin and also weak hypercharge. They are also having a very short lifetime which is almost 100,000 times shorter than that of the muon.
Neutrinos
Neutrinos are produced in a variety of interactions. Since they don’t interact electrically or strongly, they almost never interact with any other particles. They are very small in mass( a million times lighter than electrons).
Is proton a type of lepton?
No. Leptons and protons belong to the class of sub-atomic particles, but they are not the same. Leptons are particles with a half-spin. So, protons are not a type of lepton.
Are leptons and quarks similar?
Leptons and quarks belong to the same class of sub-atomic particles and have spin. But, they are different in nature. Quarks show strong interaction, for example in protons and neutrons. Leptons do not interact strongly and may interact through weak forces.
