INTEGRAL/IBIS search for e-e+ annihilation radiation from the Galactic Center Region
G. De Cesare(1), A. Bazzano(1), F. Capitanio(1), M. Del Santo(1), V. Lonjou(2), L. Natalucci(1), P. Ubertini(1), P. Von Ballmoos(2)
(1) Istituto di Astrofisica Spaziale e Fisica cosmica (IASF) - CNR, via Fosso del Cavaliere 100, 00133 Roma, Italy
(2) Centre d'Etude Spatiale des Raynnements, CNRS/UPS, B.P. 4346, 31028 Toulouse Cedex 4, France
Paper: Advances in Space Research , 2005, in press
Abstract:
Electron-positron annihilation radiation from the Galactic Center region
has been detected since the seventies, but its astrophysical
origin is still a topic of a scientific debate. We have analyzed data of
the gamma-ray imager IBIS/ISGRI onboard of ESA's INTEGRAL platform in the
e-e+ line. During the first year of the missions Galactic Center
Deep Exposure no evidence for point sources at 511 keV has been found in
the ISGRI data; the 2 sigma upper limit for resolved single
point sources is estimated to be 1.6* 10-4 ph cm-2 s-1.
Preprints available from the authors at Giovanni.Decesare@rm.iasf.cnr.it
,
or the raw TeX (no figures) if you click here.
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