We studied Xe diffusion on Nb(l 10) from 48 to 70 K using the linear optical diffraction from laser-induced Xe density gratings. The diffusion rate is characterized by an Arrhenius behavior with an activation energy of E-diff = 54 meV and a diffusivity D-0 = 1.7 x 10(-6) cm(2)/S. We also performed a density-functional theory calculation of the binding energy for Xe on Nb(l 10). Our preliminary result shows that Xe prefer on-top sites with a binding energy of 247 meV, and move by hopping over short-bridge sites with an activation energy barrier of 51 meV, in close agreement with the experimental value. (C) 2003 Elsevier B.V. All rights reserved.