Problem :
For the case of an argon plasma, the ion-neutral collision frequency is 1.3E+7 sec' and the ionization collision frequency is 1.6E+9 'EXP(-15.9/T4eV)) sec' at 133 Pa. Using the Ingold model, calculate electron temperature for the case of a plasma column (cylindrical coordinates) with radius equal to either 1 or 10 cm, and with pressure equal to either 133 Pa or 50 Pa. Assume that the sheath thickness is 5 times the electron Debye length. Fill the following table:
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T.
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R=lcm
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R=10 cm
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P = 133 Pa
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?
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7
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P=50 Pa
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7
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7
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HINT: The background gas density is directly proportional to pressure. Since the ion neutral and ionization collision frequencies are given at 133 Pa, it is easy to calculate the same values at SO Pa.
HINT: assume the plasma density to be 10" cnyl. You need that to estimate the Debye length and the thickness of the sheet.