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Introduction - Optical Monitor - Observing Program

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     The Optical Monitor (OM) onboard XMM is a Ritchey-Chrétien telescope with a diameter of 300 mm that allows to complement the X-ray data collected with the EPIC and RGS instruments with simultaneous observations in the visible and ultraviolet range (from 150 nm to 550 nm). A filter wheel allows to select the wavelength range and the images are collected with a photon-counting detector.

     For additional information about this instrument see the official web page at: http://mssls7.mssl.ucl.ac.uk/.

Optical Monitor layout

     The OM was designed and constructed by an international consortium consisting of University College London (UK), University of California at Santa Barbara (USA), Los Alamos National Laboratory (USA), Pennsylvania State University (USA) and Liège University (Belgium).

     In Belgium, the Centre Spatial de Liège (CSL) acted as a local coordinator and performed the qualification and optical calibration tests. The high-energy astrophysics group (GAPHE) of the Institut d'Astrophysique et de Géophysique (IAG) contributed to the selection of the scientific targets as well as to the in-flight calibration of the instrument. The participation of the Liège University and of the Centre Spatial is supported through a PRODEX contract with the Belgian Science Policy.

     C. Jamar (CSL) and J.-M. Vreux (IAG) are co-investigators of the OM consortium, which gave them access to Guaranteed Time for the Observing Program.