title: Relativistic nonlinear Thomson scattering as attosecond x-ray source.
abstract: Relativistic, nonlinear Thomson scattering by an electron of an intense laser field has been investigated by computer simulation. Under a laser field with a pulse duration of 20-fs full width at half maximum and an intensity of 10(20) W/cm(2), the motion of an electron is highly relativistic and generates an ultrashort radiation of 2 as with photon energies from 100 to 600 eV. An interesting modulated structure of the spectrum is observed and analyzed. A radiation produced by the zigzag motion of an electron under a linearly polarized laser has better characteristics than by a helical motion under a circularly polarized laser pulse in terms of an angular divergence and an energy spectrum. The effect of ion field in a plasma was also investigated, which shows that for a laser intensity of 10(20) W/cm(2), the ion field due to an ion density of up to 7 x 10(18) cm(-3) can be ignored during the laser pulse.
authors.affiliation: Laboratory for Quantum Optics, Korea Atomic Energy Research Institute, P. O. Box 105, Deokjin-Dong, Yuseong-Gu, Daejeon 305-600, Korea.
authors.forename: K
authors.initials: K
authors.lastname: Lee
authors.forename: Y H
authors.initials: YH
authors.lastname: Cha
authors.forename: M S
authors.initials: MS
authors.lastname: Shin
authors.forename: B H
authors.initials: BH
authors.lastname: Kim
authors.forename: D
authors.initials: D
authors.lastname: Kim