James Rodi, Gary L. Case, Michael L. Cherry, Ascension Camero-Arranz, Mark H. Finger, Peter Jenke, Colleen A. Wilson-Hodge, Vandiver Chaplin
Employing the 12 NaI detectors in the Fermi GBM, the Earth Occultation
Technique (EOT) can be used to measure the fluxes of x-ray and gamma-ray
sources. Each time a source passes behind the Earth (or emerges from behind the
Earth), a step-like feature is produced in the detector count rate. With a
predefined catalog of source positions, the times of the occultation steps can
be calculated, the individual steps fit, and the fluxes derived. However, in
order to find new sources and generate a complete catalog, a method is needed
for generating an image of the sky. An imaging algorithm has been developed to
generate all-sky images using the GBM data. Here we present imaging results
from ~2.5 years of data in the 12-25 keV and 100-300 keV energy bands.
View original:
http://arxiv.org/abs/1111.0345
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