# Quark Physics

Quarks are teeny-tiny particles that make up most of the universe's mass. They always hang out in groups of three or more and never go solo. Every quark has its own special features like an electrical charge, a baryon number, and a strange number. Scientists use the letter "q" to represent quarks. This is what we call Quark Physics.

## The baryon number and the types of quarks

The baryon number indicates if you are dealing with a particle or an antiparticle. See the following table showing the different types of quarks.

For every quark in this table, there is an antiquark. Antiquarks possess the opposite charge, baryon number, and strange number, but the same mass.

## What is the physics behind quarks?

arks a big role in lot of physical processes. They're the tiny building blocks of matter that form protons and neutrons, giving them an electrical charge. Quarks can group together to form something called hadrons, like the Pion plus and Kaon plus. And they're also involved in beta decay, which is a type of radiation. So, as you can see, quarks are pretty important in the world of science! This is what we call Quark Physics.

Protons and neutrons are both made up of three quarks, represented by the symbol qqq. The combination of up and down quarks determines what kind of particle you're dealing with. To create a proton, which has a fundamental charge of 1, you need two up quarks and one down quark. Adding the charges of these three quarks gives you a total of 1, which indicates that you're dealing with a proton. Similarly, to create a neutron with a fundamental charge of 0, you need two down quarks and one up quark. Adding the charges of these three quarks gives you a total of 0, which tells you that you're dealing with a neutron. Protons and neutrons are both baryons, which are made up of normal matter. Adding their baryon numbers gives you 1, indicating that you're dealing with a baryon consisting of normal matter. This is all part of the fascinating field of Quark Physics.

### Pion plus and kaon plus hadrons

Quarks have the ability to combine with their antimatter counterpart, called an antiquark, to form a matter-antimatter. This is seen in hadrons such as the pion plus and kaon plus. The pion plus is made up of an up quark with a charge of + ⅔ and an anti-down quark with a charge of + ⅓, resulting in a total charge of 1. Similarly, the kaon plus is made up of an up quark with a charge of + ⅔ and a strange antiquark with a charge of + ⅓, resulting in a total charge of 1. Both the pion plus and kaon plus have a baryon number of 0, indicating that they are a combination of matter and antimatter. Quarks and their antimatter counterparts are essential components in particle physics and are studied in depth in the field of Quark Physics.

### Quarks and beta decay

Beta decay is a process in which a nucleus with too many neutrons or protons undergoes a transformation. In beta minus (β −) decay, a neutron is converted to a proton, and the process creates an electron and an electron antineutrino; while in beta plus (β +) decay, a proton is converted to a neutron and the process creates a positron and an electron neutrino.

In the case of a neutron to proton conversion, one down quark must convert itself into an up quark. This conversion includes the release of an electron, which takes away the negative charge, and an antineutrino. The equation for this process is shown below:

n → p + e− + νe

The neutron has a baryon number of 1 in the upper corner and 0 as its fundamental charge in the bottom corner. The result of the decay must be a proton with a charge of 1 and an electron with a charge of -1. In this process, an antineutrino is emitted as well.

### Weak interaction and quarks

The process that converts a neutron into a proton is a type of weak interaction process. There are four types of weak interaction processes, as listed below:

1. Neutron to proton process: a neutron converts into a proton and releases an electron and an antineutrino.
2. Proton to neutron process: a proton converts into a neutron and releases a positron and a neutrino.
3. Electron capture: an atomic nucleus captures an electron, and the proton absorbs the electron. This reaction releases a neutron and a neutrino.
4. Proton and electron collision: a protonides an electron, which reaction releases a neutron and a neutrino.

In all four processes, a W+ or W- boson particle acts as a carrier of the energy. The weak interaction is responsible for these processes and is one of the four fundamental forces of nature, along with gravity, electromagnetism, and the strong interaction. The weak interaction is responsible for the decay of subatomic particles and plays a crucial role in nuclear fusion and fission reactions.

### Feynman diagram and quarks

The Feynman diagram is a way to show the interaction between particles as they emit or absorb energy while creating other particles. Let us consider the example of the beta decay of a neutron into a proton, as shown below:

The Feynman diagram for this is:

### Strange quarks and the strange number

High energy photons such as gamma rays can collide with particles, emitting other particles and radiation. In the Earth's atmosphere, they inject energy into molecules of air, creating strange quarks. However, the particles created do not separate themselves into smaller particles as quickly as scientists expected. This effect was explained by a new property called strangeness, which is indicated by the strange number. Strange numbers only change during weak force interactions.

Matter as we know it consists of quarks, which are hadrons that make up the neutron and proton. The neutron and proton are made up of positive quarks called up and down quarks. Positive quarks have a charge of + ⅔ and - ⅓. When three of them are added together into a neutron or proton, the respective combination is either 0 or 1.

Apart from neutrons and protons, there are also other particles such as the pion plus and the kaon plus, which consist of a combination of quarks and antiquarks. In contrast to neutrons and protons, they only have two quarks rather than three.

Quark physics is the study of the elementary particles that make up matter. It is a fundamental part of particle physics and helps us understand the properties of matter at the subatomic level.

## Quark Physics

What is a quark?

A quark is an elemental particle that makes up protons and neutrons.

Quarks are not made of any other particle.

How many quarks are there?

There are twelve quarks. Six of them are normal quarks, while the other six are their counterparts, known as antiquarks.