# Tag Info

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The radiation belts are thought to be produced through multiple processes. One of the original leading ideas was the concept of radial diffusion. Other ideas included energization due to low frequency waves. I have done work in this field, but only with a higher frequency electromagnetic wave called whistler mode waves. I will focus on these in my ...

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Nowadays, the answer is negligibly so. Video cameras now digitise the image as pixels in parallel using charge coupled device technology. Former technologies, however, would emit appreciable bremstrahlung from decelerating electron beams, as I now describe. Before the coming of CCD arrays, the main video technology was the scanned photocathode, also called ...

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To illustrate the difficulty of answering your question, here are the components of a local fallout model, as given in Stanford's Fallout models and radiological countermeasure evaluations (PDF link): Weapon models Condensation models Particle cloud models Distribution models Contamination models Dose models Resource models Transport system models Every ...

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I have discovered the source of the discrepancy with help from the researcher (thanks Dr. Lipinski!). It seems that many sources (including Wikipedia, the undergraduate heat transfer texts by Incropera & DeWitt and Lienhard & Lienhard) mention only breifly, or not at all, the dependence of the speed of light in the medium on the refractive index, ...

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In addition to the other answers, "bright light can never hurt your eyes" has to be false -- you up the intensity of the light enough, and the energy density can get arbitrarily high. In principle, it's possible to have light so bright that it collapses to a black hole. Before then, you'll get pair production in the light beam.

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Here are some "order-of-magnitude" arguments: Quoting https://en.wikipedia.org/wiki/Decay_heat#Spent_fuel : After one year, typical spent nuclear fuel generates about 10 kW of decay heat per tonne, decreasing to about 1 kW/t after ten years Now since this is heat, you can't convert it to electricity with 100% efficiency, the maximum possible ...

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There are many reasons why they are not used, the reasons or my explanations may not or may not be good/useful. in no particular order Alpha voltaic's are prob the best, with Pu238 or Am241 being likely candidates, though, Cm-243,244 are also options. They are superior to batteries in almost every way, but cost limits them to micro power devices. uses are ...

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The expression refers to the situation where the particle, such as an atom, containing charged constituants, is coupled to the (quantised) electromagnetic field. Then, if the atom is in an excited electronic state, it can decay to a lower state by emitting a photon (a quantum of the electromagnetic field). This process is known as radiative decay.

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I don't know what "penetration power" is or why quantum tunneling needs to be invoked. Sr-90 decays entirely via beta emission with up to $0.546\ \mathrm{MeV}$ given to the electron, and its daughter isotope similarly decays with up to $2.28\ \mathrm{MeV}$ given to the electron. These energy ranges are right around the $1.71\ \mathrm{MeV}$ of P-32, whose ...

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Yes, beta decay of Sr-90 produces a 546keV beta (note that Y-90, the daughter nucleus, is also a beta emitter, but at 2.284MeV). This energetic electron can then produce bremsstrahlung x-rays from interactions with electrons. For a given x-ray energy, lead will have some absorption coefficient - really this is no different than visible light interactions ...

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You're supposed to substitute $$E\left(x,y,z,t\right)=E_0 \sin\left(\frac{n_1\pi x}{L}\right) \sin\left(\frac{n_2\pi y}{L}\right)\sin\left(\frac{n_3\pi z}{L}\right)\sin \left(\frac{2\pi ct}{\lambda}\right)$$ into  \begin{eqnarray} 0 &=& \left(\nabla^2 - \frac{1}{c^2}\frac{\partial^2}{\partial t^2}\right) E\left(x,y,z,t\right) \\ &=& ...

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There is another effect to take into account as you accelerate your ship. It is the Unruh Effect

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Firstly, the immediate answer is no, the intensity of radiation is higher when you fly into it, like the rain situation (but the maths is different). There are three interrelated effects that you need to know about regarding your question, which are frequently omitted in popular or introductory SR: aberration of light, the full angle-dependent doppler ...

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Not only does your speed affect the amount of radiation that you receive, but this actually happens to the Earth and has been measured experimentally. You say: So basically in space, there is bound to be stray radiation, whether from the stars, or cosmic background, floating around right. and the most obvious example of this is the cosmic microwave ...

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Black body radiation is a statistical description i.e. it assumes there are enough photons that they are distributed according to Boltzmanns law. At energies high enough for a single photon to equal the total energy of the system this assumption breaks down and the black body description will no longer apply. But by the point the energy has got this high ...

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