Quantum Barrier Penetration

1
Quantum Barrier Penetration

• 1D????exp(??r-r0)
• 3D ??exp(??r-r0)/r
• ?????U-E1/2 U1/2.
• Gamov factor
• EG(pp)500KeV
• Classical suppression
• e(-E/U) e-1000.
• Quantum suppression
• Exp-(500)1/2

2
Barrier Penetration

• Classical Turning point r1.
• Ee2/r1.

3
Thermal Distribution x Gamow Penetration Factor
4
Weak Interactions in pp

• S0 factor
• Consider time two protons are within 1fm of each
  other
• Compare with n half life of 13 min
• S0 is small
• Each proton waits 20 Billion years to fuse with
  another (Astrophysics in a Nutshell, Eq 3.136)
• The sun can burn for billions of years at its
  current luminosity