Classification of particles

Question 1

What are hadrons?

Answer 1

Hadrons are a group of subatomic particles made up of quarks

Question 2

Can hadrons feel the strong nuclear force name two classes of hadrons? (quarks?)

Answer 2

Yes:
Baryons (3 quarks)
Mesons(quark and anti-quark pair)

Question 3

Name two common baryons

Answer 3

Protons and neutrons

Question 4

Name two common mesons

Answer 4

Pions and Kaons

Question 5

Have quarks ever been discovered on their own

Answer 5

No not to public knowledge in 2022

Question 6

Could a combination of quarks and anti-quarks exist for baryons?

Answer 6

No (not yet as of 2022) because all baryons and mesons have whole number charges so for baryons they are either all quarks or all anti-quarks in the case of an anti-baryon

Question 7

How does an anti-meson differ from a meson?

Answer 7

The quark becomes an anti-quark and the original anti-quark becomes a quark.

Question 8

What is the baryon number?

Answer 8

The number of baryons in an interaction and depends on whether the particle is a baryon, anti-baryon or neither

Question 9

Which particles have a baryon number of 1

Answer 9

protons, neutrons, (sigma particles tbc)

Question 10

which particles have a baryon number of 0

Answer 10

leptons and mesons

Question 11

Which particles have a baryon number of -1

Answer 11

anti-protons and anti-neutrons

Question 12

what is the baryon number for each of the quarks and name the three different types.

Answer 12

Up: 1/3
Down: 1/3
Strange:1/3

Question 13

what is the baryon number for each anti-quark?

Answer 13

-1/3

Question 14

which particle is the most stable baryon?
What does this mean in terms of decay?

Answer 14

proton
Has the longest half-life (10^32 years roughly) of any baryon and is the particle that other baryons eventually decay into

Question 15

name the most stable baryon and explain why?

Answer 15

proton is the lightest baryon and radioactive decay occurs when heavier particles decay into lighter particles

Question 16

What would violate the conservation of baryon number and why?

Answer 16

A decay of the proton as it is the lightest baryon and radioactive decay occurs when heavier particles decay into lighter particles

Question 17

what is the antiparticle of a neutral pion

Answer 17

Itself

Question 18

which particle is the lightest mesons

Answer 18

Pions

Question 19

How were pions originally discovered

Answer 19

In cosmic rays and then cloud chamber

Question 20

What are the four fundamental interactions

Answer 20

the strong force
the weak force
the electromagnetic force
the gravitational force

Question 21

What does the strong force do?

Answer 21

The strong force keeps the protons and neutrons bound together in a nucleus

Question 22

What are the four fundamental interactions caused by

Answer 22

an exchange particle/virtual particle

Question 23

What is the exchange particle of the strong force? and what does this mean?

Answer 23

Pions (are said to MEDIATE the strong nuclear force)
Strong force is transmitted between a proton and neutron by exchange of a pion

Question 24

What is peculiar about the pions mediating the strong nuclear force?

Answer 24

The pion created is a temporary violation of energy and mass conservation but since it is a virtual particle, it is not directly observed.

Question 25

Name another particle that is an exchange particle of the strong force.

Answer 25

Gluons

Question 26

Difference between pions and gluons as mediators of this force are:

Answer 26

Glouns are responsible for binding quarks together, which is called strong interaction
Pions are responsible for binding nucleons together. This is referred to as the strong nuclear force.
Collectively they are referred to as the strong force.

Question 27

How are kaons produced?

Answer 27

By the strong interaction between pions and protons

Question 28

Describe the characteristics of Kaons

Answer 28

They are heavy and unstable so normally decay into pions but kaons have long lifetime.

Question 29

Why do Kaons have unusually long lifetimes?

Answer 29

They contain a strange quark and longer lifetimes is a characteristic of particles containing strange quarks.

Question 30

How do Kaons decay and give an example of a neutral kaon decaying?

Answer 30

Decay through weak interaction
neutral kaon decaying into a positive pion and negative pion.

Question 31

What are leptons?

Answer 31

A group of fundamental (elementary) particles - not made up of any other particles so no quarks

Question 32

Which fundamental force do leptons not interact with other particles via?

Answer 32

Strong nuclear force
They do interact via the weak, gravitational or electromagnetic interactions

Question 33

Common examples of leptons

Answer 33

The electron, electron neutrino, muon and muon neutrino