title: Characteristics of light reflected from a dense ionization wave with a tunable velocity.
abstract: An optically dense ionization wave (IW) produced by two femtosecond (approximately 10/30 fs) laser pulses focused cylindrically and crossing each other may become an efficient coherent x-ray converter in accordance with the Semenova-Lampe theory. The resulting velocity of a quasiplane IW in the vicinity of pulse intersection changes with the angle between the pulses from the group velocity of ionizing pulses to infinity allowing a tuning of the wavelength of x rays and their bunching. The x-ray spectra after scattering of a lower frequency and long coherent light pulse change from the monochromatic to high order harmoniclike with the duration of the ionizing pulses.
authors.affiliation: entral Research Institute of Electric Power Industry, 2-6-1 Nagasaka, Yokosuka, Kanagawa 240-0196, Japan.
authors.forename: A
authors.initials: A
authors.lastname: Zhidkov
authors.forename: T
authors.initials: T
authors.lastname: Esirkepov
authors.forename: T
authors.initials: T
authors.lastname: Fujii
authors.forename: K
authors.initials: K
authors.lastname: Nemoto
authors.forename: J
authors.initials: J
authors.lastname: Koga
authors.forename: S V
authors.initials: SV
authors.lastname: Bulanov