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The very-high-energy gamma-ray view of the Galactic Centre as of early 2010

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 نشر من قبل Christopher van Eldik
 تاريخ النشر 2011
  مجال البحث فيزياء
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Progress in the Imaging Atmospheric Cherenkov Technique has enabled first sensitive observations of the innermost few 100 pc of the Milky Way in Very High Energy (VHE; >100 GeV) gamma rays. Observations by the H.E.S.S. instrument deliver the at date most precise data on this peculiar region, and provide an interesting view onto the acceleration and propagation of energetic particles near the Galactic Centre. Besides two point-like sources -- one coincident with the supermassive black hole (SMBH) Sgr A* -- diffuse VHE emission has been discovered within a 1 deg region around the centre. The current VHE gamma-ray view of the region is reviewed, and possible counterparts of the gamma-ray sources and the origin of the diffuse emission are discussed.



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Recent progress in pushing the sensitivity of the Imaging Atmospheric Cherenkov Technique into the 10 mCrab regime has enabled first sensitive observations of the innermost few 100 pc of the Milky Way in Very High Energy (VHE; >100 GeV) gamma rays. T hese observations are a valuable tool to understand the acceleration and propagation of energetic particles near the Galactic Centre. Remarkably, besides two compact gamma-ray sources, faint diffuse gamma-ray emission has been discovered with high significance. The current VHE gamma-ray view of the Galactic Centre region is reviewed, and possible counterparts of the gamma-ray sources and the origin of the diffuse emission are discussed. The future prospects for VHE Galactic Centre observations are discussed based on order-of-magnitude estimates for a CTA type array of telescopes.
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