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The Galactic Center region viewed by H.E.S.S

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 نشر من قبل Aion Viana
 تاريخ النشر 2011
  مجال البحث فيزياء
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 تأليف A. Viana




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The Galactic center region is the most active region in the Milky Way harboring a wealth of photon sources at all wavelengths. H.E.S.S. observations of the Galactic Center (GC) region revealed for the first time in very high energy (VHE, E> 100 GeV) gamma-rays a detailed view of the innermost 100 pc of the Milky Way and provided a valuable probe for the acceleration processes and propagation of energetic particles near the GC. H.E.S.S. has taken more than 180 hours of good-quality observations toward the GC region since the experience started in 2003. A strong and steady gamma-ray source has been detected coincident in position with the supermassive black hole Sgr A*. Besides the central pointlike source, a diffuse emission extended along the Galactic Plane has been detected within about 1$^{circ}$ around the GC. An accurate analysis of the Galactic center region suggests that the diffuse emission may dominate highest energy end of the overall GC source spectrum. I will review the current VHE view by H.E.S.S. of the GC region and briefly discuss the theoretical models which explain VHE gamma-ray emissions of the central source and the diffuse emission.



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