title: Nonequilibrium evolution of strong-field anisotropic ionized electrons towards a delayed plasma-state.
abstract: Rigorous quantum calculations of the femtosecond ionization of hydrogen atoms in air lead to highly anisotropic electron and ion angular (momentum) distributions. A quantum Monte-Carlo analysis of the subsequent many-body dynamics reveals two distinct relaxation steps, first to a nearly isotropic hot nonequilibrium and then to a quasi-equilibrium configuration. The collective isotropic plasma state is reached on a picosecond timescale well after the ultrashort ionizing pulse has passed.
authors.affiliation: Arizona Center for Mathematical Sciences, Department of Mathematics, University of Arizona, Tucson, Arizona 85721, USA. pasenow@acms.arizona.edu
authors.forename: B
authors.initials: B
authors.lastname: Pasenow
authors.forename: J V
authors.initials: JV
authors.lastname: Moloney
authors.forename: S W
authors.initials: SW
authors.lastname: Koch
authors.forename: S H
authors.initials: SH
authors.lastname: Chen
authors.forename: A
authors.initials: A
authors.lastname: Becker
authors.forename: A
authors.initials: A
authors.lastname: Jaroń-Becker
mesh_terms: D016880:Anisotropy; D003198:Computer Simulation; D004574:Electromagnetic Fields; D004583:Electrons; D007477:Ions; D008962:Models, Theoretical; D009010:Monte Carlo Method; D044367:Phase Transition; D058626:Plasma Gases / Q000737:chemistry*; D012542:Scattering, Radiation
chemical_list: D007477:Ions; D058626:Plasma Gases