Particles – Interaction
Definitions
• Boson – fundamental exchange particles.
Strong nuclear force (SNF)/Strong Interaction
• Hold protons and neutrons together in the nucleus.
• Holds quarks together to form leptons.
• Creates particles e.g. pions and kaons.
• Can cause decay of some particles.
• Exchange particle is gluon. (-not tested knowledge)
• Exchange particle between nucleons is pion.
Weak nuclear force (WNF)
• Rarely described as a ‘force’.
• Causes decay of particles.
• Allows one quark to change into another.
• Does not have to conserve strangeness, can change by +/-1.
• Exchange particle is W+ or W- .
• Exchange particle is Z0 . (-not tested knowledge)
Electromagnetic force
• Acts between charged particles, cannot act on neutral particles.
• Attractive between opposite charged particles.
• Repulsive between same charged particles.
• Exchange particle is virtual photon. (-not tested knowledge)
Gravity
• Acts between particles with mass.
• Always attractive.
• Very weak compared to others.
• Exchange particle is graviton. (-not tested knowledge)
Comparison- similarities/differences
Weak interaction has a short range due to W+,W- having a larger mass, which requires
more energy to be created, electromagnetic has infinite range as virtual photon has
almost no mass- less energy required.
Electron capture
Definitions
• Boson – fundamental exchange particles.
Strong nuclear force (SNF)/Strong Interaction
• Hold protons and neutrons together in the nucleus.
• Holds quarks together to form leptons.
• Creates particles e.g. pions and kaons.
• Can cause decay of some particles.
• Exchange particle is gluon. (-not tested knowledge)
• Exchange particle between nucleons is pion.
Weak nuclear force (WNF)
• Rarely described as a ‘force’.
• Causes decay of particles.
• Allows one quark to change into another.
• Does not have to conserve strangeness, can change by +/-1.
• Exchange particle is W+ or W- .
• Exchange particle is Z0 . (-not tested knowledge)
Electromagnetic force
• Acts between charged particles, cannot act on neutral particles.
• Attractive between opposite charged particles.
• Repulsive between same charged particles.
• Exchange particle is virtual photon. (-not tested knowledge)
Gravity
• Acts between particles with mass.
• Always attractive.
• Very weak compared to others.
• Exchange particle is graviton. (-not tested knowledge)
Comparison- similarities/differences
Weak interaction has a short range due to W+,W- having a larger mass, which requires
more energy to be created, electromagnetic has infinite range as virtual photon has
almost no mass- less energy required.
Electron capture
