Plasma dynamics of an explosive emission center - ecton of a cathode spot in external tangential magnetic field

摘要: The plasma dynamics of an explosive-emission center demonstrates the polarization in applied external magnetic field, induced by dense spherical expansion across field. additional positive space charge appears at retrograde side due to current j ϕ =σBv/c ≈105BT [A/cm2]. Probability initiation a new explosive emission increases and decreases amperian this polarization. Velocity cathode spot motion (for considered copper cathode) vretr was estimated as v retr ∼0.3·v random ·BT. For clean surface ∼104cm/s, hence ∼0.3B Gs [cm/s]. “Robson angle” function derived from simple geometrical reasons spot-cell (explosive-emission-center) polarization, i.e. ζ R =arctan(A·tanθ B ), where A≡tanα pl /cosα α = 20°–40° - plasma-jet-expansion parameter. Therefore, considering can give explanation vacuum-arc cathode-spot frames ecton model.