🧠 Remember: Weak Interaction

• All quarks and leptons experience the weak interaction

• The bosons mediating the forces are $W,Z$ which can be virtual or real

  Boson	Mass	Electric charge	Spin
  $Z^0$	$M_Z=91.2\,\rm GeV$	$q_Z =0$	$1$
  $W^+$	$M_W=80.4\,\text GeV$	$q_{W^+} =1$	$1$
  $W^-$	$M_W=80.4\,\text GeV$	$q_{W^+} =1$	$1$

Neutral current interactions

• We have the following allowed vertices for neutral current interactions

  

  

  

• They have the following conservations:

  • ✅ Electric charge

  • ✅ Lepton flavour

  • ✅ Quark flavour

Charged current interactions

• We have the following allowed vertices

  

  

  

• They have the following conservations:

  • ✅ Electric charge

  • ✅ Lepton flavour

  • ❌ Quark flavour

🗒️ Note: on notation, interactions can be draw in

$W^-$

or $W^+$

By convention we just draw

Where we draw the $W$ line vertice to represent $W^\pm$