VIRUS-W, built by the University Observatory in Munich and the Max-Planck Institute for Extraterrestrial Physics, is currently operated at the 2.7 m Harlan J. Smith Telescope of the McDonald Observatory in Texas. One of the predominant features of VIRUS-W is that it implements a so-called Integral Field Unit (IFU). Other than the usual slit at the entrance aperture of a spectrograph, an IFU delivers spectra in a two-dimensional field of view, a spectrum for every pixel in the image so to speak.
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