PMAS, the Potsdam Multi-Aperture Spectrophotometer, was developed at the Astrophysikalisches Institut Potsdam and is available as common-user instrument at the Calar Alto Observatory 3.5m Telescope since July 1st, 2002.

As a UV-visual integral field spectrophotometer, the instrument was designed specifically to explore the potential of integral field spectroscopy (IFS, also "3D") for the investigation of point sources, and for the development of crowded field 3D spectroscopy. As part of the ULTROS project, the instrument is currently being further developed to provide a "nod/shuffle" beam-switching mode for faint-object 3D spectroscopy.

Compared to other 3D instruments, PMAS has a relatively small field-of-view (8"x8"), but a large wavelength coverage for each spatial element : 2048 pixels (with 4Kx4K mosaic : 4096 pixels), corresponding e.g. to a free spectral range of ~1600 (3200) Angstroms at a spectral resolution of 3 Angstroms with a 600 gr/mm grating. To accomodate different wavelength regions and different spectral resolutions, a set of 10 diffraction gratings is available for observers, covering the full useable spectral region between 350nm and 900nm. Basic parameters of PMAS at the 3.5m Telescope are given in the table below:

In order to facilitate observing with PMAS, the P3d on-line data reduction software is available at the telescope. Using a straight-on forward graphical user interface, it is an easy task to obtain wavelength-calibrated datacubes immediately after readout of a new CCD frame. The full-fledged P3d package for final data reduction and analysis can be used with support from the PMAS team at AIP. Further support and the development of dedicated 3D data analysis software will be provided by Euro3D, a European Research Training Network, which is coordinated by AIP.

A unique feature is the availability of a cryogenic direct imaging CCD camera with a 1Kx1K, backside-illuminated CCD. This A&G camera can be equipped with up to four standard 50mm broad or narrow-band filters of the Calar Alto filter inventory. The camera is thus suitable for deep acquisition exposures of faint targets and for offset-guiding. The FOV is 3.4x3.4 arcmin^2 at a scale of 0.2 arcsec/pixel.

For more information, consult the PMAS Technical Description and Cookbook webpages.
 
 

Contact :

Martin M. Roth (PMAS team leader, AIP) : mmroth@aip.de
Nicolas Cardiel (Instrument responsible, CAHA) : cardiel@caha.es
Emil Popow (Support, AIP) : epopow@aip.de
Thomas Becker (Data Reduction Software, AIP) : tbecker@aip.de
 
 

Links :

- PMAS Homepage at Calar Alto
- Technical Description
- User Manual / Cookbook
- the Euro3D Research Training Network