Photons from black body spectra

Join the discussion
Ask a follow-up here, or get your own question answered by working scientists, mathematicians and engineers — people, not an autocomplete.
Real named experts · corrections over time · the nuance an AI answer skips
3 replies · 2K views
dgrosel
Messages
3
Reaction score
0
Hi,
I don't quite understand which are the fundamental processes for production of photons that are emitted by a "black body". Usually this is explained by considering a cavity in thermodynamic equilibrium but I am not interested in this. I am looking for a more practical description of this phenomena. I would for example like to know if this includes processes like light scattering, bremsstrahlung, cyclotron radiation,...
For example the Sun spectra is known to be close to black body spectra. But how are the photons emitted by the Sun actually produced?

Thanks!
 
Physics news on Phys.org
Hello dgrosel:

Here are a few sources of light (electromagnetic radiation) :

Thermal (heat) radiation, fission and fusion reactions, an accelerating electron (I think), an alternating electric current, a moving magnetic field, maybe the Unruh effect (behind Hawking radiation) and more generally nuclear or electron energy transitions.

In a nutshell, if a subatomic particle isn't in a ground state, it's often capable of emitting energy quanta...energy...electromagnetic radiation.

But how are the photons emitted by the Sun actually produced?

See this current related discussion:
https://www.physicsforums.com/showthread.php?p=3416597#post3416597

Where do photons come from...where do they go? VERY difficult questions.
In string theory, a piece of a string can be a photon...if it has the right energy vibrational characteristics. In QM we have the Schrödinger (wave) and the equivalent Heisenberg matrix mechanics observational based descriptions.
 
Last edited:
Hi Naty1,
thanks for your reply.

Naty1 said:
Thermal (heat) radiation, fission and fusion reactions, an accelerating electron (I think), an alternating electric current, a moving magnetic field, maybe the Unruh effect (behind Hawking radiation) and more generally nuclear or electron energy transitions.

What I am interested in is actually only the so called "thermal radiation", since this is related to black body radiation. There should probably exist some elementary processes that contribute to this type of radiation.
 
From:

http://www.windows2universe.org/sun/atmosphere/photosphere.html


"Most of the energy we receive from the Sun is the visible (white) light emitted from the photosphere. The photosphere is one of the coolest regions of the Sun (6000 K), so only a small fraction (0.1%) of the gas is ionized (in the plasma state). The photosphere is the densest part of the solar atmosphere, but is still tenuous compared to Earth's atmosphere (0.01% of the mass density of air at sea level). The photosphere looks somewhat boring at first glance: a disk with some dark spots. "

Most matter not ionized, but some is. Therefore electrons find ionized atoms from time to time and get localized and give off photons? From time to time photons find matter and eject electrons and disappear.