Description of the COMPTEL exposure plots for the combined phases
The combined COMPTEL exposure plots show the calculated effective exposure of the sky as observed
by the COMPTEL instrument onboard CGRO.
The effective exposure takes into account
To calculate the exposure of a certain region of the sky (sky pixel), the effective exposure which is given for
the pointing direction of the observation has to be folded with the response function of COMPTEL.
- the times when the earth in the field-of-view blocks part of the viewing direction (minitelescopes),
- the timeswhen data can not be received due to the unavailability of a receiving station (in the direct
telemetry mode effective since middle of Phase I),
- the times during the Sout Atlantic Anomaly passes, when COMPTEL is switched off.
The response function of COMPTEL is triangle-shaped with a linear decrease from
a maximum at the pointing direction to zero response at a distance of 50 degrees from the pointing direction.
A typical maximum effective exposure is about 40 % per observation, if the viewing direction of COMPTEL is
in the orbital plane of CGRO. The average effective viewing per observation is about 30 %.
Plots have been scaled individually so that black is always identical to zero observation, and white is adjusted
to the maximum effective exposure of this very plot.
The maps are in galactic coordinates and AITOFF projection.
Last update of this page 2011-02-16 by
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