Waveform produced by an atomic transition

[hempyelmo]

Greetings Physics Forums! This is my first post.

A physical phenomena that I know for a long time is that when an atom (let's say hydrogen) has an electron that make a quantum jump from a higher energy state to a lower it emits a photon. Suppose the hydrogen atom is isolated from the external world. Can we associate a wave with that photon and if so, what is its form? Spherical? I really need some course in quantum electrodynamics...

Thanks

 

[Meir Achuz]

It is a spherical wave, but can vary with angle, depending on the angular momentum carried by the photon.

 

[SpectraCat]

It is a spherical wave, but can vary with angle, depending on the angular momentum carried by the photon.

Not sure what you mean here ... photons always carry one unit of angular momentum, as far as I know. That is one of the principal reasons for the transition dipole selection rule for allowed transitions. Are you making a distinction between photons with different helicities (i.e. spin of +1 vs. spin of -1)?

 

[Meir Achuz]

There are other transitions besides Delta L=1 dipole transitions.
There are quadrupole and higher transitions for which the photon has orbital angular momentum in addition to its spin 1 angular momentum.