All Questions
Tagged with electromagnetic-radiation photon-emission
11
questions with no upvoted or accepted answers
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What is the relationship between emissivity $\varepsilon$ and the imaginary part of relative permittivity constant $\epsilon^{''}_{\rm r}$ if any?
In terms of the Stefan-Boltzmann law a body that does not absorb all incident radiation emits less total energy than a black body and is characterized by an emissivity $0<\varepsilon <1$ such ...
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Estimating temperature with Boltzmann relation with split emission lines
I'm trying to estimate the temperature of a plasma through the use of hydrogen lines, $H_{\alpha}$ and $H_{\beta}$ using the Boltzmann relation:
$$ \frac{ n_{2} }{ n_{1} } = \frac{ g_{2} }{ g_{1} }e^...
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How can energy conservation not be violated in stimulated emission processes?
Fermis golden rule, derived from time-dependent perturbation theory, give the rate for a quantum system, disturbed by a weak harmonic pertubation with frequency $\omega$, to transition from a state $|...
user224659
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Will an electron release energy when it is added into an atom for which electron affinity value is negative (endothermic)?
According to my understanding, when an electron is added into an atom, it emits energy in the form of photons because it is a form of de-excitation or relaxation. This is when electron affinity will ...
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Why do some electromagnetic waves have more than one photon?
I know that the energy of an EM wave is equal to nhv, where n is the number of photons, but why/how do the number of photons in a wave vary? If a single atom emits an EM wave with an energy of 100 ...
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Feynman Lectures on Physics Vol-I 32-3 Radiation damping. How does this classical result relate to QM?
The following is from https://www.feynmanlectures.caltech.edu/I_32.html#Ch32-S3
Now let us actually calculate the Q of an atom that is emitting light—let us say a sodium atom. For a sodium atom, the ...
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What are the properties of the electromagnetic radiation from a magnetron?
There are different modes of EM radiation. A bulb emits photons in a wide range of wavelengths and without polarisation. Radio waves are polarized modulated radiation.
What is about the radiation ...
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Stimulated emission semiclassical model for atom recoil
In the context of Saturated absorption spectroscopy, I'm having trouble modeling stimulated emission, and getting the result that is written in articles, such as this article. I tried to use a non-...
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Blackbody Radiation vs Emission Line spectrum
A perfect blackbody has a predicable emission pattern in terms of both intensity and color, given by Planck´s law.
Similarly, elements such as Hydrogen or Helium will emit specific wavelengths when an ...
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Can Two Electromagnetic waves cancel each other if it 180 degree phase moving in same direction?
If we can send two electromagnetic waves -180 degree out of phase- in same direction, then the interaction of this wave with air molecules will be less due to the low intensity of the combination. So,...
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Where can I find data of a UV blocking glass absorption filter absorbing the visible light and re-emitting the energy as a photon of NIR?
If I understand correctly, a UV Transmitting, visible light absorbing colored glass absorption filter absorbs the visible light energy and re-emits it as near IR. On Oct 16, 2013 in How does Infrared ...
