VIMOS - VIsible MultiObject Spectrograph


Photo: G.Sciarretta

VIMOS is a visible (360 to 1000 nm) wide field imager and multi-object spectrograph mounted on the Nasmyth focus B of UT3 Melipal. The instrument is made of four identical arms with each a field of view of7' x 8' with a 0.205" pixel size and a gap between each quadrant of~2'. Each arm is equipped with 6 grisms providing a spectral resolution range from ~200-2500 and with one EEV CCD 4k x 2k.

VIMOS operates in three different modes:Imaging (IMG), Multi-Object Spectroscopy (MOS),and with Integral Field Unit (IFU).

  • IMG: Imaging is possible in UBVRIz filters in a 4 x 7' x 8' field of view.
  • MOS: Multi-object spectroscopy is carried out using masks (one per quadrant) prepared in Paranal using a laser cutting Mask Manufacturing Unit. Depending on the grism used, the spectral resolution varies from 200 to 2500, and the observable range is from 360 to 1000 nm. The maximum number of slits per mask (quadrant) varies from ~40 at R=2500 to ~150-200 at R=200, for a field of view of 4 x 7' x 8'.
  • IFU: VIMOS is also equipped with an integral field unit made of 6400 fibers. The scale on the sky can be changed from 0.67" per fiber to 0.33" per fiber and the integral field unit can cover up 13"x 13" up to 54"x54" on sky depending on spectral resolution and spatial magnification. Spectral resolution and coverage are similar to MOS

Publications based on data obtained with the VIMOS instrument should quote the following reference paper: Le Fevre, O. et al. 2003, SPIE 4841, 1670.

Contact Information

  • Questions related to service mode observations and proposal preparation should be addressed to the User Support Department.
  • Questions related to visitor mode observations should be addressed to Paranal Science Operations
  • Please send us your comments, suggestions and report errors and inaccurate statements in the web pages and manuals.

Content of these pages

The following items are available on all the VIMOS pages, using the bar on the left.

  • Overview: a short description of the instrument
  • News: list of changes affecting the instrument and/or its pages.
  • Instrument Description: all the important parameters of the instrument.
  • Manuals: links to all the documents related to VIMOS.
  • Tools: a collection of useful tools and informations for preparing and analyzing the VIMOS observations.
  • Instrument Operations Team
  • Visitor Instructions: Instrument specific instructions for Visiting Astronomers