1.4 Classification of Particles

Question 1

What type of particle feels the strong nuclear force?

Answer 1

Hadron

Question 2

What particle is believed to be the only stable baryon?

Answer 2

Proton

Question 3

Write down the baryon number of:

a) an electron
b) an antineutrino
c) a kaon (K-meson)

Answer 3

a) 0
b) -1
c) 0

Question 4

What particles are produced when a neutron decays into a proton?

Answer 4

An electron and electron antineutrino

Question 5

What is the antiparticle of π⁰ ?

Answer 5

π⁰

Question 6

Explain what cosmic ray showers are.

Answer 6

High-energy particles produced as a result of radiation from space interacting with molecules in the atmosphere.

Question 7

What is a lepton?

Answer 7

A fundamental particle which does not experience strong nuclear force.

Question 8

What is the relative charge of an antimuon?

Answer 8

+1

Question 9

In what type of interaction are strange particles produced in pairs?

Answer 9

Strong interaction

Question 10

What special type of property do strange particles have?

Answer 10

Strange particles are always produced in pairs

Question 11

In what type of interaction do strange particles decay?

Answer 11

The weak interaction

Question 12

a) In what type of interaction is strangeness not conserved?
b) By how much can strangeness change in this type of interaction?

Answer 12

a) The weak interaction.
b) Strangeness can be changed by +1, 0 or -1.

Question 13

What properties are always conserved in particle interactions?

Answer 13

Charge, baryon number, lepton number, and strangeness.

(Energy and momentum are also conserved)