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Question about plasma

  1. Mar 25, 2008 #1
    not sure if this is in the right section but...

    What exactly causes plasma to reach such high temperatures?
  2. jcsd
  3. Mar 26, 2008 #2


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    Are you talking about astronomical plasmas or lab experiments?

    In the latter case, ionized particles are accelerated by a series of magnets. There may be other methods.

    For astronomical cases, there may also be many ways - one is the energy from a supernova explosion.
  4. Mar 26, 2008 #3
    Plasma we create here on earth. From things like hydrogen.
  5. Mar 26, 2008 #4


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    There are various means of heating a gas to cause ionization in order to make it a plasma. One method is simply to apply a sufficiently high potential difference, as in a neon lamp or fluorescent lightbuld, or an arc discharge.

    In fusion reactors like a tokamak, one can use ohmic heating in which a large current is induced in the gas, which behaves like a wind of a transformer. Other methods include radiofrequency heating in which the electrons are heated, and their energy is then transfered by collisions with ions.

    Yet another method is neutral beam heating in which gas (fuel) atoms are ionized, the ions are accelerated to several keV or 10's of keV, and then the ions are neutralized (recombined with the electrons of which they were stripped) and injected into the gas/plasma.

    Ideally, if sufficient fusion reactions can be induced, then the kinetic energy of the fusion reaction would heat the plasma, which is the goal for sustainable fusion reaction.
  6. Mar 26, 2008 #5

    Didnt know that about the gas. But im curious as to what is it in the plasma that puts it to such high temperatures?
  7. Mar 26, 2008 #6


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    One puts in energy to heat a plasma. The high temperature is a consequence of the energy content. One needs to understand the relationship of molecular/atomic/ion/electron kinetics and temperature.

    See - http://hyperphysics.phy-astr.gsu.edu/hbase/kinetic/kintem.html
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