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تسجيل مستخدم جديدDetection techniques for the H.E.S.S. II telescope, data modeling of gravitational lensing and emission of blazars in HE-VHE astronomy
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تأليف
Anna Barnacka
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This thesis presents the study of four aspects of high energy astronomy. The first part of the thesis is dedicated to an aspect of instrument development for imaging atmospheric Cherenkov telescopes, namely the Level 2 trigger system of the High Energy Stereoscopic System (H.E.S.S.). I am providing the motivation and principle of the operation of the Level 2 trigger, I am describing hardware implementation of the system and then I am evaluating expected performances. The second part of my thesis deals with the data analysis and modeling of broad-band emission of particular blazar PKS 1510-089. I am presenting the analysis of the H.E.S.S. data, together with the FERMI data and a collection of multi-wavelength data obtained with various instruments. I am presenting the model of PKS 1510-089 observations carried out during a flare recorded by H.E.S.S.. The third part of my thesis deals with blazars observed by the FERMI-LAT, but from the point of view of other phenomena: a strong gravitational lensing. This part of my thesis shows the first evidence for gravitational lensing phenomena in high energy gamma-rays. This evidence comes from the observation of a gravitational lens system induced echo in the light curve of the distant blazar PKS 1830-211. The last part concentrates on another lensing phenomena called femtolensing. The search for femtolensing effects has been used to derive limits on the primordial black holes abundance. I have used gamma-ray bursts with known redshifts detected by the FERMI Gamma-ray Burst Monitor (GBM) to search for the femtolensing effects caused by compact objects.
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