Schematic layout of the system

<p><strong>Figure 1.</strong> Schematic layout of the system. (a) Schematic view of the section from the last valve of PADReS to the experimental station, the main chamber with the sources on one side and the diagnostics on the other, and the beam dump. (b) Overview with 3D rendition, rear view. The FEL light enters chamber 4 from the far side. (1) Source chamber. (2) Doping chamber. (3) Differential pumping chamber. (4) Detector chamber. (5) Quadrupole mass spectrometer chamber. (6) Surface ionization detector chamber.</p> <p><strong>Abstract</strong></p> <p>The low density matter end-station at the new seeded free electron laser FERMI@Elettra is a versatile instrument for the study of atoms, molecules and clusters by means of electron and ion spectroscopies. Beams of atoms, molecules and helium droplets as well as clusters of atoms, molecules and metals can be produced by three different pulsed valves. The atomic and molecular beams may be seeded, and the clusters and droplets may be pure, or doped with other atoms and molecules. The electrons and ions produced by the ionization and fragmentation of the samples by the intense light of FERMI can be analysed by the available spectrometers, to give mass spectra and energy as well as angular distributions of charged particles. The design of the detector allows simultaneous detection of electrons and ions using velocity map imaging and time-of-flight techniques respectively. The instruments have a high energy/mass resolution and large solid-angle collection efficiency. We describe the current status of the apparatus and illustrate the potential for future experiments.</p>