Quarks & Anti Quarks

Question 1

How do strange particles behave in different interactions?

Answer 1

• Decays in Weak interaction

* Conserved in strong interaction

Question 2

What are some key features of strange particles?

Answer 2

• Produced in twos
• Created via the strong interaction
• Decay via the weak interaction.

Question 3

What strangeness do non strange particles have?

Answer 3

0

Question 4

What are the three types of quark?

Answer 4

• Up
• Down
• Strange

Question 5

What are quarks?

Answer 5

Quarks are the building blocks for hadrons, anti particles of hadrons are made from anti quarks.

Question 6

What is the quark composition of mesons?

Answer 6

Mesons consist of a:
• Quark
• Anti Quark

Question 7

What is the quark composition of baryons & anti-baryons??

Answer 7

Baryons:
• Three Quarks
Anti-baryons:
• Three Anti-Quarks

Question 8

What is the quark composition of a proton?

Answer 8

U-U-D

Question 9

What is the quark composition of a neutron?

Answer 9

U-D-D

Question 10

What occurs in beta decay in terms of quarks?

Answer 10

Up quark changes into a down quark.

Question 11

What occurs in beta decay in terms of quarks?

Answer 11

Up quark changes to a down quark.

Question 12

What is the quark for strangeness?

Answer 12

S

Question 13

What quarks are pions made from?

Answer 13

Combinations of:
• Up 
• Down
• Anti-up
• Anti-down

Question 14

What particle are strange quarks involved in?

Answer 14

Kaons.

Question 15

What is the strangeness of a strange quark?

Answer 15

-1

Question 16

What is the anti particle of a pion+, and kaon+ meson?

Answer 16

• Pion- is the anti particle of Pion+ meson

* Kaon- is the anti particle of Kaon+ meson.

Question 17

What is quark confinement?

Answer 17

Quarks are produced in pairs, it being impossible to get a quark by itself.

Question 18

What four properties are always conserved?

Answer 18

• Conservation of energy and charge
• Baryon Numbers
• Strangeness
• Lepton Numbers

Question 19

How is lepton number conserved?

Answer 19

In any change, the total lepton number for each lepton branch before the change is equal to the total lepton number for that branch after the change.

Question 20

How is strangeness conserved?

Answer 20

• Only way to change the type of quark is with the weak interaction.
• In any strong interaction, strangeness is always conserved.
• In Weak interaction, strangeness can change by -1, 0 or +1.

Question 21

How is baryon number conserved?

Answer 21

In any reaction, the total baryon number is conserved.