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Description
COMPTEL is both the name of the Imaging Compton Telescope on the Compton Gamma Ray Observatory (CGRO) and the name of this HEASARC database table which allows the user to select low-level data and maps produced by this instrument. Much more information on the COMPTEL instrument, data products, and data analysis techniques can be obtained from the Compton Observatory Science Support Center (COSSC) web site at <pre> <a href="https://heasarc.gsfc.nasa.gov/docs/cgro/">https://heasarc.gsfc.nasa.gov/docs/cgro/</a> </pre> and from the article in Legacy No. 7 on the HEASARC CGRO Data Archive <pre> <a href="https://heasarc.gsfc.nasa.gov/docs/journal/cgro7.html">https://heasarc.gsfc.nasa.gov/docs/journal/cgro7.html</a> </pre> Interactions in COMPTEL occur in a two stage process: First, a Compton collision occurs in one of seven (low-Z) liquid scintillators and is usually then completely absorbed in one of fourteen (high-Z) NaI(Tl) scintillators. The unusual aspect of this detector is that the location of the gamma-ray on the sky is given by an annulus and not a point. The correlation of many events enables the localization of point sources or the creation of sky maps. Time-of-flight measurements, pulse shape discrimination and anti-coincidence shields are used to reject background events. COMPTEL has a wide field of view (about 1 steradian, equivalent to a FWHM of about 40 degrees), an angular resolution under optimal conditions of about 1 degree, and an energy resolution that ranges from 5-10% at 1 MeV. During Phase 1 of the CGRO mission, COMPTEL completed the first all-sky survey in the energy range of 0.75-30 MeV (in four energy bands). In addition, COMPTEL can measure energy spectra of solar flares or bright cosmic gamma-ray bursts between 0.1-10 MeV, and neutrons from solar flares. This is a service provided by NASA HEASARC .
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