Abstract
A detailed study of the spectrum and variability of the source HESS J1745-290 in the Galactic Center (GC) region using new data from the H.E.S.S. array of Cherenkov telescopes is presented. Flaring activity and Quasi Periodic Oscillations (QPO) of HESS J1745-290 are investigated.
The image analysis is performed with a combination of a semi-analytical shower model and the statistical moments based Hillas technique. The spectrum and lightcurves of HESS J1745-290 are derived with a likelihood method based on a spectral shape hypothesis.
Rayleigh tests and Fourier analysis of the H.E.S.S. GC signal are used to study the periodicity of the source.
With three-fold increase in statistics compared to previous work, a deviation from a simple power law spectrum is detected for the first time.