zhermes said:It depends on the energy of the electron and positron. If they are low energy, the only things that can be created are photons; at higher energies there is some probability that muon-pairs will be produced, and at even higher energies even more massive particles can be produced.
As soon as the energy of the electron-positron pair exceeds the rest mass energy of a particle-anti-particle pair, I think there is some probability that it will be created.
There are numerous quantities you have to conserve; charge is one of them---which means that if a charged species is created (e.g. a muon, q = -e) another particle will also be created with the opposite charge (e.g. an antimuon, q = +e). Similarly, 'lepton number' needs to be conserved, energy, angular momentum (e.g. spin) etc etc.ravisastry said:If photons are created in annihilation, there won't be electric charge created in photons...but for Muon pairs, we have a positive and a negative muon. How can this be possible ?
zhermes said:There are numerous quantities you have to conserve; charge is one of them---which means that if a charged species is created (e.g. a muon, q = -e) another particle will also be created with the opposite charge (e.g. an antimuon, q = +e). Similarly, 'lepton number' needs to be conserved, energy, angular momentum (e.g. spin) etc etc.
Nope. It's experimentally very well established that only the total charge is conserved.ravisastry said:dont we have charge conservation for that particular charges ? like instead of sum total...how about total no of negative (or positive) charges should remain the same pre & post the event ?