A high resolution 4π multi-electron spectrometer for soft electrons

Abstract

Electrons emerging form ionizing collisions of any projectiles (ions, photons, electrons) with the particles in a supersonic jet target (atoms, clusters, molecules) are projected onto three large-area, multi-hit capable position sensitive detectors applying well controlled electric and solenoidal magnetic fields. Up to three electrons with an energy bandwidth for each between 0 eV ≤ E e ≤ 1 keV are detected simultaneously with a solid angle close to 4π. Each momentum vector (three spatial components p ei) is calculated from the measured hitting positions and time-of-flights with a resolution of Δ p ei < 2 × 10 −2 a.u.. Thus, the complete final many-electron momentum space (up to 9 momentum components) is visualized. The theoretical limits in resolution achievable with such a method is in the neV-regime. In addition, the recoil-ion momentum vector is determined simultaneously applying “conventional” recoil-ion momentum spectroscopy.