Electron-ion momentum vector coincidences in electron collisions with atoms and molecules

•Kinematically complete studies for electron impact ionization.•Recoil momentum measurements for electron impact excitation of helium int metastable states.•Full solid angle coverage of electron impact ionization for single ionization resulting in 3D cross section patterns.•Kinematically complete study for positron impact ionization.•Electron impact double ionization of helium close to threshold.•Kinematically complete studies for molecular fragmentation.