# Tag Info

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There are many ways to detect a nuclear explosion, and there are people working to detect it. The Comprehensive Nuclear-Test-Ban Treaty Organization or CTBTO is one such organization. They are using a global network called the International Monitoring System. This is capable of detecting any nuclear detonations anywhere on the Earth (underwater, or in the ...

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All the Sun's power $P$ passes uniformly through a sphere with radius of 1 AU. Calculate the total surface area of this sphere and call it $S$. The Earth's disc also has a surface area that can be calculated from its radius. Call this surface $S_E=\pi R_E^2$. The fraction of the Sun's power received by the Earth is thus: $f=P\frac{S_E}{S}$.

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I've cross checked it with some known isotopes which decay by Cluster Decay. It would appear to be that. I guess it stands for Cluster Emission.

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These sorts of calculations are part of the design process for spallation sources and are done quite carefully. The tool of choice is MCNP, which has been extensively benchmarked over many decades. MCNP is maintained by folks at LANL, which happens to have a tantalum-clad tungsten spallation target; if you are on-site at LANL you should invite someone from ...

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You might want to do some basic reading about beta decays. Wikipedia at the very least. Beta decay comes in two flavors, + and -. In both cases a neutron decays into a proton and either an electron and an antineutrino or a positron and a neutrino. The emitted electrons/positrons are sometimes called Beta radiation, and I assume this is what you're talking ...

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There are such devices, but they are rather limited in their electrical output and do require you to carry a big chunk of radioactive material around. Ironically their only commercial use was implanted pacemakers! If you are going to use radiation to make energy it's easier to use a safer alpha emmitter and just use the heat to generate electricity by the ...

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I stumbled across this question and wanted to reply to one particular part of it: Lastly, despite the Wikipedia article somewhat addressing the topic, is this problem of self-force present with other forces (e.g. gravity)? I believe it does state that standard renormalization methods fail in the case of GR and thus the problem is still present ...

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The electromagnetic self-force problem has been solved recently, see here; the gravitational self-force problem has also been solved recently, see this article.

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The thing about Feynman diagrams is that they are rotatable and that they try to maintain a direction of progression of time. In this specific circumstance, it seems time flows from bottom to top. It indicates that the proton, electron, and neutrino are products, outputs from the interaction. If rotated, the inputs and outputs would change. In that way, the ...

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