The authors describe a compact He beam apparatus developed for high resolution studies of surface structures by He diffraction and of surface vibrations by He energy-loss spectroscopy. The angular resolution is 0.135 degrees FWHM (rotation of the sample) and the He beam intensity is 1019 atoms sr-1 s-1 at the sample. The apparatus is also equipped with Auger and ultraviolet photoemission spectroscopy. Measurements of He diffraction patterns and He energy loss spectra are reported from the (1*2) Au(110) surface and provide a full characterization of the apparatus.
