I cannot wrap my head around this stuff. Sorry if long post.(adsbygoogle = window.adsbygoogle || []).push({});

I understand that emission lines come from a higher energy state dropping to a lower state. This happens at discrete energy levels, which should correspond to discrete frequencies. And the same atom should be able to absorb photons at those same energy/frequency. Yet when you look at an absorption or emission profile you see a curve (looks Gaussian) rather then delta functions. I can't understand this? Is there a probability that the atom will absorb or emit photons not at that discrete frequency?

Also recombination produces emission and do those photons have energy = to the ionization energy? Will this also be a spectrum rather then a delta function?

I also dont understand the idea of line radiation and continuum radiation. Say I have some line and it travels through a gas cloud. The cloud can absorb some of it or emit and add to it. I saw in class that theres a line absorption profile and a continuum profile. The line profile is the gaussian looking shape and the continuum profile is a constant (or practically constant). What are these? Sorry if this is a little vague

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# Trying to understand emission and absorption

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