What is Quark?

1
What is Quark?

• Composes Hadron composed of quarks
• Which includes Baryon fermions composed of 3
  quarks
• Fermions experience nuclear forces
• We study their interaction with QCD(Quantum
  Chromo-dynamics)

2
What is Quarks?

• 6 types
• Up Down Charm
• Top Bottom Strange

3
Quarks properties
Quarks Symbol Electric Charge
Up u 2/3
Down d -1/3
Charm c 2/3
Strange s -1/3
Top t 2/3
Bottom b -1/3
4
What is Quarks?

• Antiquarks particles with opposite properties
• Baryon number - To form a baryon, sum of
  composition quarks must be integer.
• Quarks all have Baryon number of 1/3, while
  antiquarks are -1/3

5
Quantum Chromo-dynamics

• States that
• Strong forces between Quarks dont decay by
  distance so they are always stuck together
• This strong force is determined by the Colour
  charge of the quarks
• (Not actual visual colour, but just three kinds
  of charges)

6
Quantum Chromo-dynamics

• 3 Quarks joins together under strong force ?
  Baryons (Baryon number 1/3 1/3 1/3 1)
• 1 Quark 1 Antiquark ? Mesons (Baryon number
  1/3 -1/3 0)
• Quarks tends to group in combination neutralize
  their colour charge

7
Pentaquarks

• Particles with 5 quarks, namely, Exotic Baryon
• First discovered, theta
• Electric charge of 1
• Strangeness of 1
• Decays into K meson ( u) and neutron (udd)