Blackbody Radiation in Optically Thick Gases?
نویسنده
چکیده
In this work, the claim that optically thick gases can emit as blackbodies is refuted. The belief that such behavior exists results from an improper consideration of heat transfer and reflection. When heat is injected into a gas, the energy is primarily redistributed into translational degrees of freedom and is not used to drive emission. The average kinetic energy of the particles in the system simply increases and the temperature rises. In this respect, it is well-know that the emissivity of a gas can drop with increasing temperature. Once reflection and translation are properly considered, it is simple to understand why gases can never emit as blackbodies.
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