Questions tagged [absorption]
A transition by which the energy of at least one photon is completely transferred to a material.
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Regarding the absorption property of a blackbody
Consider a blackbody of surface area $S_b$ and at temperature $T_b$. It is placed inside an evacuated chamber (to neglect all the effects of convection), with walls of chamber at temperature $T_c$ and ...
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X-ray absorption edge, accurate theoretical predition possible?
It is well known that in X-ray absorption spectroscopy, the absorption spectrum shows discontinuities at some critical frequencies.
Is it possible to predict locations of these jumps theoretically? I ...
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The absorption of infrared light for regular materials, like fabric wallets backpacks and clothes
I work as a brand partner for a company that produces a patch which strengthens the production of stemcells in the body.
The patches are activated with the help of the bodys own infrared radiation.
I ...
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Absorption and emission spectrum terminology
Hi everyone recently i was looking for laser crystals and since I am an autodidact i was confused by the terminology and units of the optics domain. And specialy by the absorption and emission ...
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How can the inverse of stimulated emission be distinguished from "normal" absorption?
A simple system with two energy states can absorb an incoming photon (of adequate energy) to get excited, and it can relax by either spontaneously emit a photon afterwards or get stimulated by another ...
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Is there a way to use the optical transfer-matrix method to determine the absorbance of each layer in a multilayer stack?
I've implemented the transfer-matrix method to determine the the transmittance and reflectance of a multilayer stack of thin films.
I know that (ignoring scattering) the absorbance of the entire stack ...
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What is the range of noon sun color temperature, when a light meter reports full expected sunlight (+/- epsilon)?
My question came from trying to find what uncertainty bounds, if any, I can assign to a color temperature sensor, without access to an artifact with a precisely calibrated output spectrum.
This leads ...
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Temporal absorption coefficient from complex wavenumber
A complex wavenumber $k=\beta-i\alpha$ can be defined, that when substituted into a time-harmonic solution $e^{i(\omega t - kx)}$ yields $$e^{-\alpha x}e^{i(\omega t - \beta x)}$$
The first negative ...
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Absorption spectra in films chemicals & dyes
For a science competition, we have to understand absorption spectra in films chemicals & dyes. But what is that? I've found resources on the absorption spectra of chlorophyll, but I'm unclear as ...
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Why escape peak positions are calculated using emission energy and not absorbing energy?
For a X-ray monocromatic source, escape peaks energy positions are described by the difference between the incident energy and the fluorescence ($K_{\alpha}$ for example), like $E_{Escape Peak} = E_0 -...
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Einsteins Coefficient of Absorption in solid state
What solid state parameter determines the probability of absorption (Einsteins coefficient B) in a material? Is it material dependent?
I think, I cannot say bandgap. Because if I have a source having ...
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What happens after bulk gold absorbs a photon with its energy at the band gap or higher (wavelength < 500 nm)?
As is explained in the answers of this question: Why are most metals gray/silver? nicely, the responsible transition occurs between the 5d orbital and the 6s orbital, which is relativistically shrunk ...
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How much gas is needed to produce absorption lines?
I am trying to know whether it would be possible to do an undergraduate laboratory experiment to measure absorption lines produced by a gas. The idea is to have a background source of light with a ...
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Aren't places where geodesics end singularities?
So of course when stuff falls into black holes, the geodesic for anything ends in that singularity. However, isn't it technically true that a light ray that originates from the sun and then hits the ...
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What determines the wavelength in absorption?
When looking at absorption or reflectance spectra, say in the range of 400nm to 2500nm, you can see peaks (or dips) at certain wavelengths, that are characteristic for the material absorbing and ...