We study the field-ionization threshold behavior when a Rydberg atom is ionized by a short single-cycle pulse field. Both hydrogen and sodium atoms are considered. The required threshold field amplitude is found to scale inversely with the binding energy when the pulse duration becomes shorter than the classical Rydberg period, and, thus, more weakly bound electrons require larger fields for io...

We study the time evolution of the wave function of a particle bound by an attractive d-function potential when it is subjected to time-dependent variations of the binding strength ~parametric excitation!. The simplicity of this model permits certain nonperturbative calculations to be carried out analytically both in one and three dimensions. Thus the survival probability of bound state uu(t)u,...

A secondary electrospray ionization (SESI) method was developed as a nonradioactive ionization source for ion mobility spectrometry (IMS). This SESI method relied on the gas-phase interaction between charged particles created by electrospray ionization (ESI) and neutral gaseous sample molecules. Mass spectrometry (MS) was used as the detection method after ion mobility separation for ion identi...

Interstellar Polycyclic Aromatic Hydrocarbons (PAH) are expected to be strongly processed by Vacuum Ultra-Violet (VUV) photons. Here, we report experimental studies on the ionization and fragmentation of coronene (C24H12), ovalene (C32H14) and hexa-peri-hexabenzocoronene (HBC; C42H18) cations by exposure to synchrotron radiation in the range of 8-40 eV. The results show that for small PAH catio...

Abstract We review the semiclassical two-step model for strong-field ionization. The describes quantum interference and accounts ionic potential beyond perturbation theory. discuss formulation implementation of this model, its further developments, as well some applications. reviewed applications include holography with photoelectrons, multielectron polarization effects in ionization by an inte...

The 363.8 nm photoelectron spectrum of the iminodiazomethyl anion has been measured. The anion is synthesized through the reaction of the hydroxide ion (HO-) with 1 H-1,2,3-triazole in helium buffer gas in a flowing afterglow ion source. The observed spectrum exhibits well-resolved vibronic structure of the iminodiazomethyl radical. Electronic structure calculations have been performed at the B...

Evolution of atomic ionization into the strong-field limit offers the opportunity to study the fundamentals of atom-laser interaction. In this study, we report on high precision measurements of the ion and electron distributions from laser-excited helium and neon atoms which reflect the changing continuum dynamics as the ionization process evolves into the pure tunneling regime. The experiments...

Sang-Kil Son (손상길), Robert Thiele, Zoltan Jurek, Beata Ziaja, and Robin Santra Center for Free-Electron Laser Science, DESY, Notkestrasse 85, 22607 Hamburg, Germany The Hamburg Centre for Ultrafast Imaging, Luruper Chaussee 149, 22761 Hamburg, Germany Institute of Nuclear Physics, Polish Academy of Sciences, Radzikowskiego 152, 31-342 Kraków, Poland Department of Physics, University of Hamburg,...