title: Energetic proton acceleration and bunch generation by ultraintense laser pulses on the surface of thin plasma targets.
abstract: Energetic proton acceleration from concave targets, the front of which were irradiated with 40 fs laser pulses with an intensity of 10(20)W/cm(2), has been studied as a function of the depth of the concave shape. Three kinds of targets, a triangular concave target, a circular concave target and a parabolic concave target are considered. When the depth of the concave shape was varied, the peak proton energy showed a maximum. The underlying mechanism for the existence of a maximum peak proton energy is presented by tracing the proton trajectory. It is concluded that a parabolic concave target is the best, among the targets considered, for accelerating a proton beam, since a proton beam from a parabolic concave target goes through the strongest electric field.
authors.affiliation: Faculty of Technology, Tokyo University of Agriculture and Technology, Koganei-shi, Tokyo 184-8588, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Okada
authors.forename: A A
authors.initials: AA
authors.lastname: Andreev
authors.forename: Y
authors.initials: Y
authors.lastname: Mikado
authors.forename: K
authors.initials: K
authors.lastname: Okubo