Spin of photons/gamma ray transitions

[freeman2]

When I look at a nuclear level scheme, there are many gamma ray transitions from energy levels of say, spin 4 to spin 2. However, my understanding was that photons carry spin 1, and so conservation of angular momentum would say that you can only change the spin of a level by 1. What am I missing here? Can photons carry any integer spin, eg 1,2,3...?

 

[Vanadium 50]

The photon can be emitted with orbital angular momentum relative to the emitting nucleus.

 

[sir-pinski]

You are correct in saying that photons carry spin 1. However, in the case of gamma ray transitions, the spin change is not caused by the photons themselves, but rather by the interaction between the nucleus and the surrounding environment.

This interaction can result in the nucleus gaining or losing angular momentum, leading to a change in its spin. This change in spin is then accompanied by the emission or absorption of a photon, which carries away the excess or deficit of angular momentum.

So while photons themselves cannot carry higher spin values, they can still be involved in spin-changing processes through their interactions with other particles.

Furthermore, gamma ray transitions are not the only way in which a nucleus can change its spin. Other processes such as beta decay or nuclear reactions can also result in spin changes, without the involvement of photons.

In summary, the spin changes observed in nuclear level schemes are a result of the complex interactions between the nucleus and its environment, which can involve the emission or absorption of photons. So, there is no contradiction with the conservation of angular momentum principle.