Hmmmm... I hadn't meant "up and down" to apply to electron velocities but it is an interesting thought.

Is the broadening greater with greater tempuratures, up to a point, I suppose?

It would be interesting to see someone do a portrayal of the random walk of a single progenitor gamma ray as it starts in the core of the sun and travels to the surface, passing through the various shells, resulting in its more than 5 thousand colorful offspring.

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Lighten up! This is a stellar board! Author: duh.

"The Sun, with all the planets revolving around it, and depending on it, can still ripen a bunch of grapes as though it had nothing else in the universe to do..." Author: Galileo supposedly.

There are only three reasons that the Planck function and the Maxwellian distribution are different. One is in the way they fill in energy states, which is different partly because photons are relativistic and a Maxwellian is not. The second is in the fact that you generally have a fixed number of electrons that are sharing the energy, whereas photons appear and disappear permanently, in respose to the temperature. Finally, electrons are "fermions" and photons are "bosons", which means you can only put one electron in one state, but any number of photons. Put together, those three effects are the only differences, otherwise it's all just counting the states available at any total energy. Detailed mechanisms don't matter at all, given enough time-- that's the beauty of thermodynamics in a nutshell.

It would just be a guess, but wouldn't the two distributrion curves (Planck and Maxwellian) be similar, nevertheless?

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Lighten up! This is a stellar board! Author: duh.

"The Sun, with all the planets revolving around it, and depending on it, can still ripen a bunch of grapes as though it had nothing else in the universe to do..." Author: Galileo supposedly.

Only where e^{(h nu)/(k_BT)} >> 1.

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papageno


"Why waste time learning, when ignorance is instantaneous?" - Hobbes (Calvin and Hobbes)

"It's all about context!" - Vince Noir (The Mighty Boosh)

"I've never heard of such a brutal and shocking injustice that I cared so little about!" - Zapp Brannigan (Futurama)

George. Yes, the Doppler broadening increases with temperature. I was taking a tour of MIT's plasma fusion center, and somebody asked the guide what kind of "thermometer" they used...as a joke...to measure the plasma temperature. A short discourse on lines becoming bands ensued...interesting. Pete.

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A third rate theory forbids
A second rate theory explains after the fact
A first rate theory predicts...A. Lomonosov

That is pretty interesting and indicative of the complexity of those things. Too bad the surrounding air doesn't just glow blue as an indication of strength.

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Lighten up! This is a stellar board! Author: duh.

"The Sun, with all the planets revolving around it, and depending on it, can still ripen a bunch of grapes as though it had nothing else in the universe to do..." Author: Galileo supposedly.