Free-electron lasers produce extremely brief, coherent, and bright laser-like photon pulses
that allow to image matter at atomic resolution and at timescales faster than the …

Free-electron lasers are fourth-generation light sources that deliver extremely intense (>
1012 photons per pulse), ultrashort (∼ 10− 14 s= 10 fs) light pulses at up to kilohertz …

Coincidence spectroscopy is a powerful spectroscopic method addressing the recording of
more than one particle involved in an ionization process simultaneously. In the current …

Five-fold differential cross sections (5DCS) for electron impact ionization of a diatomic
molecule have been explored experimentally as a function of molecular alignment. Using H …

Spectral probes for the CH+, OH+, and SiH+ hydride molecular ions that play key roles in
astrophysics and plasma processes are presented. The merged-beam technique at the …

A cryogenically cooled linear electrostatic ion beam trap for use in photoelectron-
photofragment coincidence (PPC) spectroscopy is described. Using this instrument, anions …

We report the X-ray absorption of isolated H3O+ cations at the O 1s edge. The molecular
ions were prepared in a flowing afterglow ion source which was designed for the production …

This paper reports an advanced study of the excited ionic states of the gas-phase nitrogen
molecule in the binding-energy region of 22–34 eV, combining ultrahigh-resolution resonant …

The photofragmentation of the water cation H 2 O+ through dicationic states has been
studied at 35.0±0.2 nm (35.4±0.3 eV) and 21.8±0.2 nm (56.8±0.5 eV) with a crossed ion …

We discuss the ionization of aligned hydrogen molecules into their ionic ground state by 200
eV electrons. Using a reaction microscope, the complete electron scattering kinematics is …