A high angular resolution grazing incidence atom optics apparatus has been utilized for previous studies on matter-wave diffraction or reflection under grazing incidence condition [ref]. A schematic of the apparatus is depicted in Figure 3. Either continuous, cold He or D2 beam is formed by supersonic expansion through 5 \(\mu\)m of the orifice at stagnation pressure P0 and source temperature T0. Liquid helium is used to cool down the source.