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Here are the neutron decay Feynman diagram : A free neutron will decay by emitting a W-, which produces an electron and an antineutrino. and the diagram for neutrino neutron scattering : This interaction is the same as the one at top since a W+ going right to left is equivalent to a W- going left to right. In the quantum mechanical ...


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The boson serves as an "interaction propagator" particle. Namely it is short lived and serves as the "carrier" of the weak force that governs the beta decay. Similar cases are in the strong interactions where qluons play this role or in electromagnetism, where the electromagetic force id mediated by photons. You dont have to study quantum field theory to ...


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The half life can in principle be determined using Fermi's Golden Rule. Well, this calculates transition probabilities per unit time, but the half life is simply derived from the transition probability. So if you know the initial and final wavefunctions and the appropriate operator then yes you can calculate the half life. However in practice nuclei are far ...


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This is a simplified version of radiative transfer equation, in which the scattering source term is treated as a source function $j_{\nu}$. Thus, in the solution, the optical distance from the scattering source $j_{\nu}(s')$ to the detecting position $s$ is written as a function of the two position/path variables to emphasize the idea that the specific ...


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Generally Tesla coild are fairly safe from the point of view of X-ray generation. You could potentially test for it using a sealed can of camera film with a high ISO rating, placing it in the vicinity of the coil while it is operating, and then developing it to see if it is fogged. However, a bigger problem might be ultraviolet light, ozone and nitrogen ...


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If we were able to have a quantum mechanical model for nuclei that needed no experimental input, then the half lives of unstable nuclei would be computed utilizing the fully known wavefunctions. An approximation to this ideal is the shell model, and there are papers in the literature using the wavefunctions of the model to calculate lifetimes that fit the ...


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You speak of fading over seconds. This is not likely to be a result of filament glow in a mains voltage domestic light as they cool very fast. There is unlikely to a sodium vapour lamp in your bathroom either. Most LED lights will turn on and off pretty fast as storage capacitors are expensive to waste. Possibly a thick filament (low voltage) halogen ...


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i will give a more general answer unless other information is added (then i can update) It would depend on type of antenna, the frequency/wavelength of transmission and how this wavelength compares relative to the height of the wheel and rpm (i would say the height mostly). if the wavelength is comparable to the height of the wheel it will have serious ...


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You said that the lamp gave off a yellow glow, so it is possible that it could be a sodium lamp. However, your conception about light intensity and wavelength is a bit off. If the lamp that you are speaking of gives off a monochromatic light source, it is most likely using an electrical current to excite the atoms of a single element. When excited, ...


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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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