| Fundamental particles that cannot be broken down any further and do not experience the strong nuclear force. | Leptons |
| What is the key difference between leptons and hadrons? | Leptons are fundamental particles that do not experience the strong nuclear force, while hadrons are made of quarks and do experience the strong nuclear force. |
| Particles that are made up of quarks and experience the strong nuclear force. They are divided into baryons, antibaryons, and mesons. | Hadrons |
| What are baryons, antibaryons, and mesons made of? | Baryons are made of 3 quarks, antibaryons are made of 3 antiquarks, and mesons are made of a quark and an antiquark. |
| A property that shows whether a particle is a baryon (1), an antibaryon (-1), or not a baryon (0). Baryon number is always conserved in particle interactions. | Baryon Number |
| What does a baryon number of 1, -1, and 0 represent? | 1 represents a baryon, -1 represents an antibaryon, and 0 means it is not a baryon. |
| The only stable baryon. All baryons eventually decay into protons either directly or indirectly. | Proton |
| Which baryon is stable and what happens to other baryons? | The proton is the only stable baryon; all other baryons eventually decay into a proton. |
| A property that shows whether a particle is a lepton (1), an antilepton (-1), or not a lepton (0). Lepton number is always conserved in particle interactions. | Lepton Number |
| What are the possible values of lepton number and what do they indicate? | 1 for a lepton, -1 for an antilepton, and 0 for non-leptons. |
| A particle sometimes referred to as a "heavy electron" that decays into an electron. | Muon |
| What happens to a muon after it decays? | A muon decays into an electron. |
| Particles that are produced by the strong nuclear interaction but decay via the weak interaction. | Strange Particles |
| How are strange particles produced and how do they decay? | Strange particles are produced by the strong nuclear interaction and decay through the weak interaction. |
| A property of particles that must be conserved in strong interactions but can change by 0, +1, or -1 in weak interactions. | Strangeness |
| What must happen to strangeness in strong and weak interactions? | Strangeness must be conserved in strong interactions, but in weak interactions, it can change by 0, +1, or -1. |
| A type of strange particle that decays into pions through the weak interaction. | Kaons |
| What do kaons decay into and how? | Kaons decay into pions via the weak interaction. |
| A process where scientists work together internationally, especially in particle physics due to the high cost and large amounts of data produced by particle accelerators. | Scientific Collaboration |
| Why is scientific collaboration important in particle physics? | Due to the high cost of building and running particle accelerators and the large amounts of data they produce, international collaboration is essential. |
| Quarks are fundamental particles that make up hadrons. | Quarks |
| What are quarks? | Quarks are fundamental particles which make up hadrons. |
| There are three types of quarks you need to know: Up (u), Down (d), and Strange (s). | Types of Quarks |
| What types of quarks do you need to know? | You need to be aware of three types of quark: up (u), down (d), and strange (s). |
| Charge: +2/3 e Baryon Number: +1/3 Strangeness: 0 | Up Quark Properties |
| What are the properties of the up quark (u)? | The up quark (u) has a charge of +2/3 e, a baryon number of +1/3, and strangeness of 0. |
| Charge: -1/3 e Baryon Number: +1/3 Strangeness: 0 | Down Quark Properties |
| What are the properties of the down quark (d)? | The down quark (d) has a charge of -1/3 e, a baryon number of +1/3, and strangeness of 0. |
| Charge: -1/3 e Baryon Number: +1/3 Strangeness: -1 | Strange Quark Properties |
| What are the properties of the strange quark (s)? | The strange quark (s) has a charge of -1/3 e, a baryon number of +1/3, and strangeness of -1. |
| Mesons are particles formed from quark combinations. | Mesons |
| Quark combination(s): u-bar(u) or d-bar(d) Charge: 0 Strangeness: 0 | π⁰ Particle |
| What is the charge and strangeness of the neutral pion (π⁰)? | The neutral pion (π⁰) has a charge of 0 and strangeness of 0. |
| Quark combination(s): u-bar(d) Charge: +1 Strangeness: 0 | π⁺ Particle |
| What is the quark combination for the charged pion (π⁺)? | The charged pion (π⁺) has a quark combination of u and bar(d). |
| Quark combination(s): bar(u)-d Charge: -1 Strangeness: 0 | π⁻ Particle |
| What is the quark combination for the charged pion (π⁻)? | The charged pion (π⁻) has a quark combination of bar(u) and d. |
| Quark combination(s): d-bar(s) or bar(d)-s Charge: 0 Strangeness: ±1 | k⁰ Particle |
| What is the quark combination for the neutral kaon (k⁰)? | The neutral kaon (k⁰) can be a combination of d and bar(s) or bar(d) and s. |
| Quark combination(s): u-bar(s) Charge: +1 Strangeness: +1 | k⁺ Particle |
| What is the quark combination for the charged kaon (k⁺)? | The charged kaon (k⁺) has a quark combination of u and bar(s). |
| Quark combination(s): bar(u)-s Charge: -1 Strangeness: -1 | k⁻ Particle |
| What is the quark combination for the charged kaon (k⁻)? | The charged kaon (k⁻) has a quark combination of bar(u) and s. |
| As all baryons decay into protons, a neutron will decay into a proton. The decay of a neutron into a proton can be represented as: n → p + e⁻ + νe | Neutron Decay Equation |
| What happens to a neutron during decay? | A neutron (n) decays into a proton (p), emitting an electron (e⁻) and an electron antineutrino (νₑ). The equation is: n → p + e⁻ + νₑ. |
