Boosting Nuclei Spin: The Role of Angular Momentum & Circularly-Polarized Light

[gildomar]

I know that in order to create a high-spin nucleus, that you slam a nucleus into the target nucleus off-center so that when they fuse, it has a large angular momentum (relatively speaking). However, can't you add angular momentum to the target nucleus by instead just shining circularly-polarized light onto it?

 

[Astronuc]

I know that in order to create a high-spin nucleus, that you slam a nucleus into the target nucleus off-center so that when they fuse, it has a large angular momentum (relatively speaking). However, can't you add angular momentum to the target nucleus by instead just shining circularly-polarized light onto it?

As in circularly polarized gamma ray? What energy level is necessary to change the spin of a nucleon, or set of nucleons? Consider that the target is a nucleus, rather than the atom (atomic electrons).

http://www.physik.fu-berlin.de/einrichtungen/ag/ag-heyn/Teaching/docs/vorlesung_12_1_10.pdf

 

[mfb]

I know that in order to create a high-spin nucleus, that you slam a nucleus into the target nucleus off-center so that when they fuse, it has a large angular momentum (relatively speaking).

Well, it is not possible to focus beams with that precision. You get all sorts of collisions, some of them are off-center.

However, can't you add angular momentum to the target nucleus by instead just shining circularly-polarized light onto it?

If you hit the right frequency for a transition, I would expect that this is possible, at least in theory.

 

[gildomar]

@Astronuc - I figure that it would need to be a gamma ray, but I'm not sure, since from what I gather, finding the proper energy for a rotationally excited state is rather complicated due to the issues you mentioned. But it might be possible with a fair amount of number-crunching.

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@mfb - I kind of figured that bit about the off-center collisions, since bunches of particles are used in beams anyway. Not to mention while the focusing magnets are pretty good, I didn't think that they can focus something the size of a nucleus to hit another nucleus precisely, even ignoring Heisenberg uncertainty for a moment.

So you haven't heard of doing it that way before? I haven't been able to find anything like it from research that I've done, but I wouldn't want to be copying someone else's work if they've already done it.