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I need urgent help! we have a beam made of some neutrons and some photons. I thought about the beryllium polycrystaline but I'm not really sure it could work. The beam has an energy of 2 MeV moreless. Sorry for my spoken english.
For the reflection of gamma rays, I checked here:
- Bragg reflection of photons with a really tiny angle.
That's what I tried to to give at a second glance over the problem. However V50 pointed out that this is not helpful because the matterial's electrons will absorb the photons. It is true that neutrons radiation will not be completely gone, but you can suppress it somehow against the photons if my initial point is correct (that photons won't interact that much with the small Z atoms). However the interacting neutrons will generate further gamma-radiation.
- A thin layer of (amorphous?) material with low Z - neutrons will either pass through nearly unaffected or get a large deflection angle, while most photons will pass through roughly in their initial direction. This does not give a nice neutron-free beam of photons but it leads to some separation.
Are you sure about it? I think magnetic moment in a magnetic field will only make the moment to oscillate. If you want to apply a magnetic field for this purpose, I'd suggest to try a strongly varying magnetic field (like the Stern Gerlach experiment for electrons) . But I still think that this can only dispress the beam and neutrons are much heavier than electrons (that's why you will need a much larger gradient for the mag.field).While neutrons have no electric charge, they do have a magnetic moment. With a strong enough magnetic field and large enough distance you could deflect the neutrons while leaving photons totally unaffected. I'm not sure how strong it would have to be for 2 MeV neutrons though, possibly unfeasible.
No problem, just stick your detector on a satellite at the L2 Lagrange point and you're all set! :)Neutrons have a magnetic moment of ~10-26J/T. If you somehow manage to get a field gradient of 1000 T/m, this gives a force of 10-23 N or an acceleration of 6000 m/s2. To get a deflection by 1° at ~20,000km/s neutron speed, you need ~300km/s or 50s acceleration time, which gives a convenient length of 1 million kilometers for your deflecting structure.
It's not working that way, because you will have to apply that magnetic field for that length of path... and 1000T/m sounds a very large number ... A smaller gradient would make the distance much larger... and at 16mil km you will already get the neutrons decay....No problem, just stick your detector on a satellite at the L2 Lagrange point and you're all set! :)
Look upthread.I think I should start by mentioning I'm not qualified to answer this question. Would it be possible to scatter the neutrons without effecting the photons by passing the beam through something like Radon gas?
Neutrons interact with nuclei, and photons interact with electrons. You won't find nuclei without electrons.
I see. Thanks.Look upthread.