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INTEGRAL/IBIS search for e-e+ annihilation radiation from the Galactic Center Region

G. De Cesare·A. Bazzano·F. Capitanio·M. Del Santo·V. Lonjou·L. Natalucci·P. Ubertini·P. Von Ballmoos
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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 $2 σ$ upper limit for resolved single point sources is estimated to be $1.6\times 10^{-4} ph cm^{-2} s^{-1}$.

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G. De Cesare, A. Bazzano, F. Capitanio, M. Del Santo, V. Lonjou, L. Natalucci, P. Ubertini, P. Von Ballmoos. 2005-01-07. INTEGRAL/IBIS search for e-e+ annihilation radiation from the Galactic Center Region. https://doi.org/10.1016/j.asr.2005.01.015

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