Tunneling and Pair Creation

Most recent answer: 11/15/2009

Q:
Does a tunneling event create pairs of oppositely charged particles just like pair production? I guess I really just don't see the difference.
- Laura (age 17)
Buffalo
A:
Tunneling is the name given to the quantum mechanical phenomenon of a particle overcoming a potential barrier.  Pair production is the process of creating a particle-antiparticle pair.  Both processes conserve charge.   An example of non pair producing tunneling is the decay of certain nuclei by alpha particle emission such as U238 --> Th234 + He2.  Both charge and energy are conserved but no pairs are produced.  
An example of a pair production process is γ + Pb --> Pb + e- + e+ where the γ is a high energy photon. 

LeeH

(published on 11/15/2009)