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arXiv · 0709.3729

Localising the H.E.S.S. Galactic Centre point source

C. van Eldik·O. Bolz·I. Braun·G. Hermann·J. Hinton·W. Hofmann
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Abstract

Observations by the H.E.S.S. system of imaging atmospheric Cherenkov telescopes provide the most sensitive measurements of the Galactic Centre region in the energy range 150 GeV - 30 TeV. The vicinity of the kinetic centre of our galaxy harbours numerous objects which could potentially accelerate particles to very high energies (VHE, > 100 GeV) and thus produce the Gamma-ray flux observed. Within statistical and systematic errors, the centroid of the point-like emission measured by H.E.S.S. was found to be in good agreement with the position of the supermassive black hole Sgr A* and the recently discovered PWN candidate G359.95-0.04. Given a systematic pointing error of about 30'', a possible association with the SNR Sgr A East could not be ruled out with the 2004 H.E.S.S. data. In this contribution an update is given on the position of the H.E.S.S. Galactic Centre source using 2005/2006 data. The systematic pointing error is reduced to 6'' per axis using guiding telescopes for pointing corrections, making it possible to exclude with high significance Sgr A East as the source of the VHE Gamma-Rays.

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C. van Eldik, O. Bolz, I. Braun, G. Hermann, J. Hinton, W. Hofmann. 2007-09-24. Localising the H.E.S.S. Galactic Centre point source. https://doi.org/10.1088/1742-6596/110/6/062003

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