Neutral vanadium sulfide clusters are generated by the reaction of seeded hydrogen sulfide in a helium carrier gas with laser ablated vanadium metal within a supersonic nozzle. The exiting clusters are expanded into a vacuum in a molecular beam and are ionized by both ultraviolet (UV) and vacuum UV (VUV) laser radiation. The generated ions are detected by a time of flight mass spectrometer. Wit...

RF ionization rates for mixtures of air with bariurn are computed using a Fokker-Planck code. It is shown that there is an optimum mixing ratio of barium to air, significantly ower than unity, which maximizes the ionization rate for a given value of incident RF power density and frequency. Rocket injection of barium at a selected height reduces ignificant/y the RF breakdown threshold for the mi...

We investigate the ionization of HeNe from below the He 1s3p excitation to the He ionization threshold. We observe HeNe+ ions with an enhancement by more than a factor of 60 when the He side couples resonantly to the radiation field. These ions are an experimental proof of a two-center resonant photoionization mechanism predicted by Najjari et al. [Phys. Rev. Lett. 105, 153002 (2010)]. Furtherm...

Measurements of the sputtering yield of solid O2 by 25–240-keV H + show that it is double valued in its dependence on electronic stopping power. We propose that this is because the electronic sputtering yield is dominated by repulsion of ions in the ionization track of the projectile which, at low velocities, is augmented near the surface due to the additional ionization resulting from electron...

The balance of the linear photon momentum in multiphoton ionization is studied experimentally. In the experiment argon and neon atoms are singly ionized by circularly polarized laser pulses with a wavelength of 800 and 1400 nm in the intensity range of 10(14)-10(15)  W/cm2. The photoelectrons are measured using velocity map imaging. We find that the photoelectrons carry linear momentum correspo...

1. radioactive decay and ionization as it relates to effects of radiation 2. that the primary target for the induction of biological effects is DNA 3. the broad similarities in radiation responses among organisms 4. the wide variation in responses among organisms 5. the generation of free radicals and their role in biological effects from radiation 6. repair of damage from radiation 7. mis-repa...

The H(3)(+) molecular ion has been used by Oka and collaborators to trace the rate of ionization by cosmic rays in the interstellar medium. More energetic cosmic rays also produce diffuse γ-radiation. Now that several supernova remnants (SNRs) have been identified as γ-ray sources, it is possible to use spectroscopy of molecular ions to search for enhanced ionization rates that would pinpoint t...

We construct hydrogen atmosphere models for strongly magnetized neutron stars in thermodynamic equilibrium, taking into account partial ionization. The presence of bound states affects the equation of state, absorption coefficients, and polarizability tensor of a strongly magnetized plasma. Therefore the partial ionization influences the polarization vectors and opacities of normal electromagne...