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What Is Non-thermal Radiation?

  1. Sep 5, 2011 #1
  2. jcsd
  3. Sep 5, 2011 #2
    I don't understand the point, and would withhold any judgements before reading and understanding the paper, though a quick search suggests it was a flash-in-pan article that generated press because of it's sexy title - most web references I found all come from about the same timeframe, four years ago. But generally, non-thermal radiation is radiation generated by non-thermal processes, i.e. by something that is not simply hot and emitting radiation characteristic of it's temperature. One example would be synchrotron radiation.
  4. Sep 6, 2011 #3
    This is mostly just semantics. We describe thermal radiation as a specific range of electromagnetic radiation that is experienced, in the presence of matter, as heat. However, all electromagnetic radiation carries energy proportionate to its frequency. For instance, microwave electromagnetic energy is very good at heating up TV dinners.

    The most energetic electromagnetic energy seems to be Gamma Rays. You really really do not want to observe very many of these up close and personal. ALL electromagnetic energy is simply photons with specific frequencies. The various frequencies interact with matter in wildly different ways.

    The electromagnetic spectrum, however, is vast.
  5. Sep 6, 2011 #4
    Rays versus Rays. Science had not done a good job of differentiating electromagnetic "rays" from other types of rays. Most importantly, Cosmic Rays ARE NOT electromagnetic rays. They are "energetic charged subatomic particles". X-rays are, however, electromagnetic rays that have a wavelength in the range of 0.01 to 10 nanometers.

    Cosmic rays are very very bad things. Probably worse then even gamma electromagnetic radiation. A single cosmic ray [for instance a single proton] carries as much energy as a baseball thrown at 100 miles per hour. Happily these tend to crash into atmospheric particles that then cascade in a variety of forms.

    I invite you to ponder how much velocity a single proton would need to equal a baseball at 100 miles per hour. E=mc2 suddenly become comprehensible.
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