The Oxford SWIFT integral field spectrograph

We present the design of the Oxford SWIFT integral field spectrograph, a dedicated I and z band instrument (0.65 mu m - 1.0 mu m at R similar to 4000), designed to be used in conjunction with the Palomar laser guide star adaptive optics system (PALAO, and its planned upgrade PALM-3000). It builds on two recent developments (i) the improved ability of second generation adaptive optics systems to correct for atmospheric turbulence at wavelengths <= 1 mu m, and (ii) the availability of CCD array detectors with high quantum efficiency at very red wavelengths (close to the silicon band edge). Combining these with a state-of-the-art integral field unit design using an all-glass image slicer, SWIFT's design provides very high throughput and low scattered light. SWIFT simultaneously provides spectra of similar to 4000 spatial elements, arranged in a rectangular field-of-view of 44 x 89 pixels. It has three on-the-fly selectable pixel scales of 0."24, 0."16 and 0."08. First light is expected in spring 2008.