The region of the Galactic anticenter, including the Crab Nebula, was observed during a balloon flight of the University of New Hampshire Directional Gamma-Ray Telescope employing the coded-aperture imaging technique to image celestial gamma-radiation between 160 keV and 9.3 MeV. The background systematics are treated with a simple and relatively straightforward correction procedure. The results demonstrate that the coded-aperture procedure is a viable approach for imaging not only point sources of radiation, but also extended sources of emission. The results for the Crab's photon spectrum are consistent with a power-law spectrum. Upper limits on the flux levels of line emission at 405 keV and 1050 keV and on the flux from the X-ray binary source A0535 + 26 and diffuse Galactic emission from the anticenter region are derived.
European Southern Observatory (ESO)
Digital Object Identifier (DOI)
M.L. McConnell, P.P. Dunphy, D.J. Forrest, E.L. Chupp, and A. Owens, GAMMA-RAY OBSERVATIONS OF THE CRAB REGION USING A CODED-APERTURE TELESCOPE, 1987, Ap. J., 321, 543.