We investigate discharge inception in air, in uniform background electric fields above and below the breakdown threshold. We perform 3D particle simulations that include a natural level of background ionization in the form of positive and − O2 ions. In background fields below breakdown, we use a strongly ionized seed of electrons and positive ions to enhance the field locally. In the region of ...

Using a simple model of strong-field ionization of atoms that generalizes the well-known 3-step model from 1D to 3D, we show that the experimental photoelectron angular distributions resulting from laser ionization of xenon and argon display prominent structures that correspond to electrons that pass by their parent ion more than once before strongly scattering. The shape of these structures ca...

Quasi-static models of barrier suppression have played a major role in our understanding of the ionization of atoms and molecules in strong laser fields. Despite their success, in the case of diatomic molecules these studies have so far been restricted to fields aligned with the molecular axis. In this paper we investigate the locations and heights of the potential barriers in the hydrogen mole...

the ionization effects of charged particles produced in neutron interactions for boron neutroncapture therapy are considered here using srim monte carlo code. the estimated values of these effects ina plexiglas acrylic phantom are shown to agree well with the available experimental values in high boronconcentration areas. as expected, the ionization effects from lithium and alpha particles are ...

We have discovered theoretically that ionization of a one-dimensional quantum well by an ultrashort subcycle ~d-like! electromagnetic pulse results in photoelectrons propagating both along the field and in the opposite direction in well-separated shells whose velocities reflect quasiresonances in the ionization continuum. For both a quantum well and a three-dimensional hydrogenlike atom, a unip...

We present velocity map imaging measurements of photoelectrons in coincidence with ions produced via strong field molecular ionization. Our measurements, in conjunction with electronic structure and Stark shift calculations, allow us to assign several features in the low energy portion of the photoelectron spectrum to different molecular electronic continua (ionic states). Furthermore, we are a...

< We characterize the chemical composition of aerosols collected

1964 B E C K E Y reported about a combined field ionisation/electron impact source1 the commercial version of which is shown in Fig. 1 2. Vhe vapour to be analyzed enters the source via an inlet line. However such inlet is suitable only for sampes of not too low volatility. For the qualitative analysis of organic compounds of very low volatility evaporation out of an oven (direct inet) in the i...

background: the present work aims to study the out-of-field photon calculation accuracy of a commercial treatment planning system (tps), oncentra, for three-dimensional conformal radiotherapy (3d-crt) and intensity modulated radiation therapy (imrt) treatment techniques from elekta synergy medical linear accelerator. materials and methods: accuracy of individual out-of-field dose components was...

We report time-resolved electron emission in experiments on ionization of rubidium Rydberg atoms (n=90) by few-cycle radio-frequency (RF) (1-10 MHz) pulses. The electron emission occurs in multiple bursts and strongly depends on the carrier-envelope phase as well as the duration and amplitude of the RF pulses. Remarkably, ionization is observed during a series of cycles with the same amplitude....