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seen Jul 4 at 20:43

Jul
4
comment Usage of the terms Raman, Stokes and anti-Stokes scattering
@Timitry I think there might be different conventions here. I think in some fields, Brillouin scattering is seen as a type of Raman scattering, while in others they are seen as separate.
Jul
4
comment Usage of the terms Raman, Stokes and anti-Stokes scattering
@garyp Yes, and Brillouin scattering can also be Stokes or anti-Stokes, depending on whether the energy is lost and or gained. So technically, Stokes scattering could refer to either Stokes Raman scattering or Stokes Brillouin scattering.
Jul
4
revised Usage of the terms Raman, Stokes and anti-Stokes scattering
grammar
Jul
4
answered Usage of the terms Raman, Stokes and anti-Stokes scattering
Jul
3
comment Could Legolas actually see that far?
@Kyle Yes, I think your answer was good. I just wanted to add some more relevant physical considerations. The one thing that I doubt in your answer is that seeing would be better in the vertical due to more uniform density and temperature. As I understand, the problem with seeing is not at all the large scale vertical inhomogenities of the atmosphere, but small scale turbulence. Most of the turbulence is in the lower parts of the atmosphere; I would assume that the boundary layer dominates. This is at most 1-2 km thick, so our 24 km would mean 12-24 times the vertical path in this.
Jul
3
comment Could Legolas actually see that far?
@Kyle Another worry would be aerosol extinction. Certainly, visibility beyond 24 km does occur in non-poluted areas on earth, but it should not be taken for granted. As for using shorter wavelengths, there is basically no light below 300 nm in the atmosphere due to absorption by the ozone layer. Middle-Earth probably also has an ozone layer since it harbors life on land. Maybe Legolas eyes have a built-in light source for UV, but wavelengths shorter than 250 nm would probably not make it the 48 km back and forth due to absorption by molecular oxygen.
Jun
16
comment Can the hot combustion products from a large flame be in “non-local thermal equilibrium”
I really appreciate this input, but unfortunately it will probably not bring me much closer to a clear answer to my question. The kinetic theory modelling would probably be a bit out of my league. Temperature gradients and other limitations of my geometric assumptions are definitely error sources that I have not ruled out. The idea of a non-Boltzmann distribution, is one of several explanations I'm considering. Unfortunately, I will not have the time to solve my problem. For the time being, I will have to leave this on the ever-growing heap of "things I wish I understood better".
Jun
13
comment Can the hot combustion products from a large flame be in “non-local thermal equilibrium”
I realize that the actual flame might be a partially ionized gas, but I am trying to measure the radiation from the exhaust slightly downwind from the flame so I am assuming that electrons and ions have recombined. Of course I cannot be totally sure of this, but I guess emission signatures of ions and free electrons should not be expected to be remotely similar to that of, for instance, water molecules. For this reason, I don't believe that this is what I'm seeing. Or are you suggesting that the two-temperature distribution of the plasma would somehow carry over to the recombined molecules?
Jun
8
awarded  Promoter
Jun
5
comment Computer parsable table of nuclides
I'm glad you found it useful. I think my search terms were simply: text file list of nuclides
Jun
5
comment Does the temperature of water determine how much heat will be removed from air used to evaporate it?
This answer does not take into account the enthalpy of evaporation, which accounts for most of the heat absorption.
Jun
5
answered Does the temperature of water determine how much heat will be removed from air used to evaporate it?
Jun
4
comment Computer parsable table of nuclides
By googling, I found this little project: github.com/jhykes/nuclide-data, which seems to include a list similar to what you describe (nuclear-wallet-cards.txt.gz). The fields are not explained but their meaning seem rather intuitive. The list seem to come from this place: nndc.bnl.gov/wallet where it is only available as a pdf. Perhaps the pdf can help explain any ambiguities.
Jun
4
awarded  Student
Jun
4
comment What would happen if I was in the centre of the Earth?
Gravitation is not at its maximum at the center of the Earth. In fact gravitation cancels out at the center. The pressure from all the stuff above you, however, is at its maximum.
Jun
4
asked Can the hot combustion products from a large flame be in “non-local thermal equilibrium”
Jun
4
answered Projectile motion - ball hit 180m/s at 45 degrees, what is the hang time?
Jan
11
awarded  Yearling
Jan
3
answered What does the decay constant mean?
Jun
20
answered Why cellphone cameras don't have optical zoom