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PMAS: The Potsdam Multi Aperture Spectrophotometer. II. The Wide Integral Field Unit PPak

Andreas Kelz·Marc A. W. Verheijen·Martin M. Roth·Svend M. Bauer·Thomas Becker·Jens Paschke·Emil Popow·Sebastian F. Sanchez·Uwe Laux
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Abstract

PPak is a new fiber-based Integral Field Unit (IFU), developed at the Astrophysical Institute Potsdam, implemented as a module into the existing PMAS spectrograph. The purpose of PPak is to provide both an extended field-of-view with a large light collecting power for each spatial element, as well as an adequate spectral resolution. The PPak system consists of a fiber bundle with 331 object, 36 sky and 15 calibration fibers. The object and sky fibers collect the light from the focal plane behind a focal reducer lens. The object fibers of PPak, each 2.7 arcseconds in diameter, provide a contiguous hexagonal field-of-view of 74 times 64 arcseconds on the sky, with a filling factor of 60%. The operational wavelength range is from 400 to 900nm. The PPak-IFU, together with the PMAS spectrograph, are intended for the study of extended, low surface brightness objects, offering an optimization of total light-collecting power and spectral resolution. This paper describes the instrument design, the assembly, integration and tests, the commissioning and operational procedures, and presents the measured performance at the telescope.

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Andreas Kelz, Marc A. W. Verheijen, Martin M. Roth, Svend M. Bauer, Thomas Becker, Jens Paschke, Emil Popow, Sebastian F. Sanchez, Uwe Laux. 2005-12-22. PMAS: The Potsdam Multi Aperture Spectrophotometer. II. The Wide Integral Field Unit PPak. https://doi.org/10.1086/497455

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