Английская Википедия:Dreicer field

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The Dreicer field (or Dreicer electric field) is the critical electric field above which electrons in a collisional plasma can be accelerated to become runaway electrons. It was named after Harry Dreicer who derived the expression in 1959[1] and expanded on the concept (i.e. runaway generation) in 1960.[2] The Dreicer field is an important parameter in the study of tokamaks to suppress runaway generation in nuclear fusion.[3][4][5]

The Dreicer field is given by[6][7]

<math>E_D = \frac{1}{4\pi\epsilon_0^2} \frac{ne^3 \ln\Lambda}{m_ev_{Te}^2}</math>

where <math>n</math> is the electron density, <math>e</math> is the elementary charge, <math>\ln\Lambda</math> is the Coulomb logarithm, <math>\epsilon_0</math> is the vacuum permittivity, <math>m_e</math> is the electron mass and <math>v_{Te}</math> is the electron thermal speed. It was derived by considering the balance between the electric field and the collisional forces acting on a single electron within the plasma.[6][8]

Recent experiments have shown that the electric field required to accelerate electrons is significantly larger than the theoretically calculated Dreicer field.[9][10][11] New models have been proposed to explain the discrepancy.[8][12]

References

Шаблон:Reflist


Шаблон:Plasma-stub