title: Conical emission from laser plasma interactions in the filamentation of powerful ultrashort laser pulses in air.
abstract: We performed detailed experimental and numerical investigations of the conical emission (CE) accompanying the filamentation of powerful ultrashort laser pulses in air. It was found that the CE originates from self-phase modulation in the plasma produced by the pulse during propagation. The experiment and the simulation agree on the essential features of the CE: The CE angle decreases with increasing wavelength and is independent of the position along the filament, and there is no CE at Stokes-shifted wavelengths.
authors.forename: O G
authors.initials: OG
authors.lastname: Kosareva
authors.forename: V P
authors.initials: VP
authors.lastname: Kandidov
authors.forename: A
authors.initials: A
authors.lastname: Brodeur
authors.forename: C Y
authors.initials: CY
authors.lastname: Chien
authors.forename: S L
authors.initials: SL
authors.lastname: Chin