title: Current clamp at zero level in JT-60U current hole plasmas.
abstract: It is found that no current is driven in a central region of a tokamak plasma once the central current density becomes nearly zero ("current hole"), in spite of high electric conductivity, at the current drive by a toroidal electric field and a radio-frequency wave in experiments on the JT-60U tokamak. This is a new, stiff, self-organized structure of a magnetic field in an axisymmetric toroidal plasma.
authors.affiliation: Japan Atomic Energy Research Institute, Naka Fusion Research Establishment, Ibaraki-ken.
authors.forename: T
authors.initials: T
authors.lastname: Fujita
authors.forename: T
authors.initials: T
authors.lastname: Suzuki
authors.forename: T
authors.initials: T
authors.lastname: Oikawa
authors.forename: A
authors.initials: A
authors.lastname: Isayama
authors.forename: T
authors.initials: T
authors.lastname: Hatae
authors.forename: O
authors.initials: O
authors.lastname: Naito
authors.forename: Y
authors.initials: Y
authors.lastname: Sakamoto
authors.forename: N
authors.initials: N
authors.lastname: Hayashi
authors.forename: K
authors.initials: K
authors.lastname: Hamamatsu
authors.forename: S
authors.initials: S
authors.lastname: Ide
authors.forename: H
authors.initials: H
authors.lastname: Takenaga