# Worksheet: The Conservation of Baryon Number

In this worksheet, we will practice determining the baryon number of composite particles and sets of particles and whether given interactions conserve baryon number.

**Q1: **

What is the baryon number of a charm antiquark?

- A
- B0
- C
- D+1
- E

**Q3: **

A tetraquark is a hypothetical particle that is made up of four quarks. If a tetraquark had the composition , what would its baryon number be?

**Q4: **

Which of the following particles have a baryon number of ?

- down quark
- down antiquark
- antielectron
- tauon
- tau neutrino
- tau antineutrino
- antiproton
- neutron
- photon

- ATau neutrino and down quark
- BAntielectron and neutron
- CTauon and down antiquark
- DAntiproton
- EPhoton, neutron, and tau antineutrino

**Q5: **

Which of the following particles have a baryon number of 1?

- electron
- neutron
- top quark
- D meson
- delta baryon
- electron neutrino
- proton
- B meson
- charm quark

- ANeutron, top quark, and D meson
- BProton, neutron, and delta baryon
- CProton, B meson, and charm quark
- DTop quark, B meson and D meson
- EElectron neutrino and charm quark

**Q6: **

What is the baryon number of an electron neutrino?

**Q7: **

What is the baryon number of a top quark?

- A
- B
- C
- D0
- E

**Q8: **

Which of the following particle interactions does **not** conserve baryon number?

- Avi
- Bv
- Ci
- Dii and iv
- Eiii and v

**Q9: **

A is a meson that is made up of an up quark and a down antiquark. What is the baryon number of a ?

**Q10: **

Which of the following particles have a baryon number of ?

- pion
- down quark
- photon
- up antiquark
- proton
- neutron
- strange antiquark
- bottom quark
- electron

- AStrange antiquark and electron
- BDown quark and bottom quark
- CPion and photon
- DUp antiquark and proton
- EElectron and neutron

**Q11: **

Which of the following particles have a baryon number of 0?

- proton
- top quark
- electron
- B meson
- down antiquark
- tauon
- mu neutrino
- delta baryon
- up quark

- AB meson, electron, mu neutrino, and tauon
- BTop quark, electron, mu neutrino, and tauon
- CDown antiquark, delta baryon, and up quark
- DUp quark, delta baryon, and B meson
- ETauon, mu neutrino, and top quark

**Q12: **

What is the baryon number of a muon?

**Q13: **

Which of the following particles have a baryon number of ?

- tauon
- down antiquark
- kaon
- strange quark
- up antiquark
- muon
- photon
- tau neutrino
- top antiquark

- ADown antiquark, up antiquark, and top antiquark
- BTau neutrino, photon, and kaon
- CKaon, photon, and up antiquark
- DMuon, tauon, and strange quark
- EStrange quark and top antiquark

**Q14: **

A Xi baryon is a particle that is made up of one up quark and two strange quarks. What is the baryon number of a Xi baryon?

**Q15: **

The following equation shows a proton and an antiproton annihilating to produce a gamma-ray photon,

What is the total baryon number before this interaction takes place?

What is the total baryon number after this interaction takes place?

**Q16: **

The following equation shows a sigma baryon decaying into a lambda baryon and a pion,

What is the total baryon number before this interaction takes place?

What is the total baryon number after this interaction takes place?

**Q17: **

The following equation shows a particle interaction that would **not** conserve baryon number,

What is the total baryon number before this interaction takes place?

What is the total baryon number after this interaction takes place?

**Q18: **

The following equation shows a lambda baryon decaying into a proton and a pion.

What is the total baryon number before this interaction takes place?

What is the total baryon number after this interaction takes place?

**Q19: **

The following equation shows a particle interaction that would **not** conserve baryon number.

What is the total baryon number before this interaction takes place?

What is the total baryon number after this interaction takes place?