Does a single nucleus in a lattice emit thermal radiation?


If so, how many photons are emitted, one (or more) for each proton? one or more for each proton on same axis? Is the frequency of the photon(s) exactly the number of oscillations per second?

For example, does an atom of golt emit 79 photons ? Consider the oscillation of a nucleus on the z- axis, in what direction travel(s) photon(s)?


The answer excludes the contribution of nuclei in thermal radiation, yet wiki says...

Thermal radiation is a direct result of the random movements of atoms and molecules in matter. Since these atoms and molecules are composed of charged particles (protons and electrons), their movement results in the emission of electromagnetic radiation, which carries energy away from the surface.

...that protons are actively involved. Can anyone explain what produces thermal radiation?


Atoms emit radiation, and absorb it, thermally. The nuclear PART of an atom, however, is not easily excited, in the sense of deformation of the nucleus. Such an 'excited state' for a nucleus, because of the strong nuclear forces, is unlikely to be as small as (typical) thermal energies. At room temperature (0.02 electron volt, roughly) the chance of making a nucleus transition to its lowest excited state (200,000. electron volt, order of magnitude) is very small. Thermal photons (infrared) and nuclear excitation transitions (gamma rays) are just too different.

For practical purposes, at 'normal' temperatures, nuclei are noninteracting with thermal radiation, basically meaning that they're transparent.

Simple kinetic energy of a molecule in a gas IS mainly the kinetic energy of one or a few nuclei, and there IS some interaction with radiation, but it is largely due to the electrons. It is electronic states that are seen in thermal radiation in gasses. The nucleus just wanders slowly as it is attracted by the thermal motion of negative charges around it.


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