Integral field spectroscopy on the WIYN telescope using a fiber array

A fiber optic array, called DensePak, has been built for the WIYN 3.5 meter telescope located on Kitt Peak, Arizona. DensePak incorporated the use of existing instruments at WIYN to provide a low-cost option for integral field spectroscopy. The array consists of 91, 310 mu m diameter fibers bonded into a 7 x 13 rectangle with fibers spaced at 400 mu m center-to-center. The array provides spatial coverage on the sky of approximately 30 x 45 are-seconds at the WIYN F/6.4 Nasmyth focus. The fiber bundle feeds the same bench spectrograph as that used for the Hydra multi-object spectrograph which provides many configuration options. DensePak has been used successfully in several scientific programs where mapping of spectral characteristics of extended objects such as galaxies, planetary nebulae, and comets is desired. The options of low to high resolution spectroscopy with DensePak allow two-dimensional spatial measurements of abundances, velocity kinematics, and line ratios to be obtained. Proven success of DensePak at WIYN has led to consideration of future upgrades to expand scientific capability through improved spatial resolution.