Evaluation of a 256 x 256 Si:As IBC detector array for astronomy

256 x 256-element IBC Si:As arrays have been evaluated for applications in IR astronomy from space-borne platforms. Basic figures of merit were measured at IR flux levels simulating those expected in space-based astronomical observations. Results include dark current less than 20 e(-)/s, G-eta as high as 3.8, eta/beta of 20%, and read noise below 100 rms(e(-)).