1) "In the field of plasma physics, because of the high temperatures encountered and the electromagnetic nature of the phenomena involved, it is customary to express temperature in electronvolts (eV) or kiloelectronvolts (keV), where 1 eV = 11,604 K. In the study of QCD matter one routinely meets temperatures of the order of a few hundred MeV, equivalent to about 10^12 K." Source and further information: http://en.wikipedia.org/wiki/Temperature 2) "Plasma temperature is commonly measured in kelvins or electronvolts, and is an informal measure of the thermal kinetic energy per particle. In most cases the electrons are close enough to thermal equilibrium that their temperature is relatively well-defined, even when there is a significant deviation from a Maxwellian energy distribution function, for example due to UV radiation, energetic particles, or strong electric fields. Because of the large difference in mass, the electrons come to thermodynamic equilibrium among themselves much faster than they come into equilibrium with the ions or neutral atoms. For this reason the "ion temperature" may be very different from (usually lower than) the "electron temperature". This is especially common in weakly ionized technological plasmas, where the ions are often near the ambient temperature. Based on the relative temperatures of the electrons, ions and neutrals, plasmas are classified as "thermal" or "non-thermal". Thermal plasmas have electrons and the heavy particles at the same temperature i.e. they are in thermal equilibrium with each other. Non-thermal plasmas on the other hand have the ions and neutrals at a much lower temperature (normally room temperature) whereas electrons are much "hotter". Temperature controls the degree of plasma ionization. In particular, plasma ionization is determined by the "electron temperature" relative to the ionization energy (and more weakly by the density) in a relationship called the Saha equation. A plasma is sometimes referred to as being "hot" if it is nearly fully ionized, or "cold" if only a small fraction (for example 1%) of the gas molecules are ionized (but other definitions of the terms "hot plasma" and "cold plasma" are common). Even in a "cold" plasma the electron temperature is still typically several thousand degrees Celsius. Plasmas utilized in "plasma technology" ("technological plasmas") are usually cold in this sense." Source and further information: http://en.wikipedia.org/wiki/Plasma_%28physics%29#Temperatures 3) "The following set of parameters, for example, provides a 10 million degree Kelvin hydrogen plasma temperature with a density-time product of 10 13 particle-seconds/cm 3 , which is suitable for use as a hard x-ray source: V.perspectiveto.12,500 volts I.perspectiveto.74,000 amperes L.perspectiveto.1.5 cm D.perspectiveto.67 μm Risetime.perspectiveto.2.7×10^-8 seconds Pulse Duration.perspectiveto.2.2×10^-8 seconds " Source and further information: http://www.freepatentsonline.com/4759894.html 4) "Fusion requires temperatures about 100 million Kelvin (approximately six times hotter than the sun's core). At these temperatures, hydrogen is a plasma, not a gas. Plasma is a high-energy state of matter in which all the electrons are stripped from atoms and move freely about. The sun achieves these temperatures by its large mass and the force of gravity compressing this mass in the core. We must use energy from microwaves, lasers and ion particles to achieve these temperatures." Source and further information: http://science.howstuffworks.com/fusion-reactor.htm/printable