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Materials of this type often form sheathes that satisfy a criterion named for Bohm. The namesake frequency of these substances is given in mks by the electron charge times the square root of the quantity number density over permittivity times electron-ion reduced mass and their namesake waves are also named for Langmuir, who discovered them. They are quasi-neutral in a Debye sphere, the radius of which, the Debye length, characterizes their charge shielding; however, many of the atoms in matter of this phase are ionized. FTP, name these collections of dissociated electrons and ions, the so-called fourth phase of matter.
Science