title: Effect of radial-electric-field polarity on wire-array Z-pinch dynamics.
abstract: The formation of plasma in wire-array Z-pinch experiments was found to depend upon the polarity of the radial-electric field near the wires. Reversing the radial-electric field midway along the length of an array resulted in the ablation rate of one-half of the array being reduced by 50%, significantly delaying the start of its implosion and altering its acceleration towards the axis. The observed phenomena cannot be explained by the standard magnetohydrodynamic models of array behavior, suggesting that effects such as electron emission may be important, especially during wire initiation.
authors.affiliation: Imperial College, Blackett Laboratory, Prince Consort Road, London SW7 2BZ, United Kingdom.
authors.forename: S N
authors.initials: SN
authors.lastname: Bland
authors.forename: S V
authors.initials: SV
authors.lastname: Lebedev
authors.forename: J P
authors.initials: JP
authors.lastname: Chittenden
authors.forename: D J
authors.initials: DJ
authors.lastname: Ampleford
authors.forename: S C
authors.initials: SC
authors.lastname: Bott
authors.forename: J A
authors.initials: JA
authors.lastname: Gómez
authors.forename: M G
authors.initials: MG
authors.lastname: Haines
authors.forename: G N
authors.initials: GN
authors.lastname: Hall
authors.forename: D A
authors.initials: DA
authors.lastname: Hammer
authors.forename: I H
authors.initials: IH
authors.lastname: Mitchell
authors.forename: J B A
authors.initials: JB
authors.lastname: Palmer