Optical Monitoring Camera
The Optical Monitoring Camera (OMC) is a standard optical refractor enhanced with baffles and covers, that is part of the INTEGRAL (International Gamma-Ray Astrophysics Laboratory) Payload. The OMC observes the optical emission of objects and dedicated to fine spectroscopy.
The Optical Monitoring Camera consists of a passively cooled CCD (2055 x 1056 pixels, imaging area: 1024 x 1024 pixels) working in frame transfer mode. The CCD is located in the focal plane of a 50 mm (diameter) lens including a Johnson V-filter to cover the 500 – 600 nm (CCD: 850 nm) wavelength range. The OMC is mounted close to the top of the INTEGRAL payload module structure.
The OMC consists of 3 sub-systems:
- the optical system (based on a 6-lens objective mounted in a titanium alloy barrel)
- the baffle (consist in a 600mm length aluminium alloy cylinder surrounding the optical system and including internal vanes to provide the necessary straylight reduction)
- the cover system (consists of a door mechanism and a forebaffle. The door is closed on ground and during launch to prevent the optics from contamination. The mechanism was operated only once in flight).
The OMC observes the optical emission from the prime targets of the Integral main gamma-ray instruments with the support of the X-Ray Monitor JEM-X. The OMC offered the first opportunity to make long observations in the optical band simultaneously with those at X-rays and gamma-rays. This capability provided invaluable diagnostic information on the nature and the physics of the sources over a broad wavelength range. Multi-wavelength observations are particularly important in high-energy astrophysics where variability is typically rapid. The wide band observing opportunity offered by Integral is of unique importance in providing for the first time simultaneous observations over seven orders of magnitude in photon energy for some of the most energetic objects in the Universe, Supernova explosions, active binary systems, black hole candidates, high energy transients, serendipitous sources and gamma-ray bursts.