[en] Full text: The Cu(110) surface sputtered with 1 keV Ar+ ions at different temperatures has been studied by Reflectance Difference Spectroscopy (RDS) and Scanning Tunneling Microscopy (STM). After sputtering at room temperature, the surface state related RDS signal at 2.1 eV remains almost constant while the optical anisotropy around 4.3 eV, however, is modified dramatically. In contrast, sputtering at 45 K and 120 K removes the 2.1 eV peak completely with an ion dose as low as 10E13 ions /cm². The change in the optical anisotropy around 4.3 eV is similar to that at room temperature. Annealing experiments show that the 2.1 eV RDS peak recovers already at 250 K whereas for a full recovery of the 4.3 eV signal an annealing temperature larger than 600 K is required. The different behavior indicates that different types of annealing processes are involved. Indeed, STM images allow to assign the change in the RDS signal to different types of surface morphologies and defects: the 2.1 eV peak originating from the surface state transition is very sensitive to local imperfections of the surface layer like adatoms and local roughness, whereas the bulk related peak at 4.3 eV is more sensitive to strain induced by subsurface defects and dislocations created by ion bombardment. (author)