Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
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Showing 1 to 18 of 18 for “"H.E.S.S"”.
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Crab flare observations with H.E.S.S. phase II
The H.E.S.S. array is a third generation Imaging Atmospheric Cherenkov Telescope (IACT) array. It is located in the Khomas Highland in Namibia, and measures very high energy (VHE) gamma-rays. In Phase I, the array started data taking in 2004 with its four identical 13 m telescopes. Since then, …
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Sub-Bogenminuten-genaue Positionen von TeV-Quellen mit H.E.S.S.
Gamma-Strahlen-Experimente, die die abbildende Cherenkov-Technik verwenden, haben eine relativ moderate Winkelaufloesung von typischerweise 0.05 Grad bis 0.1 Grad pro Ereignis. Der Schwerpunkt einer Punktquelle kann allerdings wesentlich genauer bestimmt werden. Bei starken Quellen kann der …
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Novel Atmospheric Monitoring for the H.E.S.S. site and its Industrial Applications
This thesis concerns the atmospheric monitoring instrumentation for the H.E.S.S. (High Energy Stereoscopic System) gamma-ray telescope site and the adaptation of such instruments for commercial use. The effect of the atmosphere on the H.E.S.S. telescopes' response has been demonstrated and the …
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A detailed study of the gamma-ray supernova remnant RX J1713.7-3946 with H.E.S.S.
The H.E.S.S. telescope system -- an array of four imaging atmospheric Cherenkov telescopes situated in Namibia -- aims at exploring non-thermal processes in the universe by means of very-high-energy (VHE) gamma rays. Its large field of view combined with unprecedented sensitivity enables detailed …
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Photon reconstruction for the H.E.S.S. 28 m telescope and analysis of Crab Nebula and galactic centre observations
In the presented thesis, the most advanced photon reconstruction technique of ground-based γ-ray astronomy is adapted to the H.E.S.S. 28 m telescope. The method is based on a semi-analytical model of electromagnetic particle showers in the atmosphere. The properties of cosmic γ-rays are …
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Absolute Energiekalibration der abbildenden Cherenkov-Teleskope des H.E.S.S. Experiments und Ergebnisse erster Beobachtungen des Supernova-Überrests RX J1713.7-3946
Die HESS-Kollaboration betreibt in Namibia ein System von 4 abbildenden Cherenkov-Teleskopen, die Cherenkov-Licht aus Luftschauern nachweisen, welche von Teilchen aus der kosmischen Strahlung induziert werden. Für diese Teleskope wurde mit Komponenten aus der Automatisierungsindustrie ein …
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Determination of the suitability of MT Gamsberg in Namibia for millimetre wave stronomy by measurements of the precipitable water vapour
Precipitable Water Vapour (PWV) is the amount of water vapour in the atmospheric column above a location equivalent to the amount of liquid precipitation that would result if all the water vapour in the column was condensed. Water vapour is the main source of opacity in the Earth’s atmosphere at …
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A new population of very high-energy gamma-ray sources detected with H.E.S.S. in the inner part of the Milky Way
The H.E.S.S., experiment (High Energy Stereoscopic System) is an array of four imaging Cherenkov telescopes designed to detect gamma-rays in the energy domain above 100 GeV. The telescopes utilise the stereoscopic approach, in which particle showers in the atmosphere are observed by several …
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Very High Energy Gamma-Rays from Binary Systems
This thesis presents a study of the very high energy (VHE) gamma-ray emission from X-ray binary systems using the H.E.S.S. imaging atmospheric Cherenkov array. The historical background and basic principles of ground-based gamma-ray astronomy are briefly reviewed and an overview of the design and …
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Entwicklung der Spiegelmechanik, Eichung der Kamera und erste Ergebnisse zum Nachweis hochenergetischer gamma-Strahlung aus Richtung des Krebsnebels und PKS 2155-304 mit dem ersten H.E.S.S.-Teleskop
Im Juni 2002 ging das erste von 4 Cherenkovteleskopen des H.E.S.S.-Experiments in Betrieb. Das einzelne Teleskope hat eine Gesichtsfeld von 5 und eine segmentierte Spiegelfläche von 107 m, bestehend aus 380 Einzelspiegeln. Um die notwendige Stabilität und Positioniergenauigkeit der Einzelspiegel zu …
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Very high energy emission and multi-wavelength campaigns of the BL Lac object PKS 2155-304.
This thesis is concerned with multi-wavelength observations of the prominent southern hemisphere high energy BL Lac object, (HBL), PKS 2155-304. After a general introduction covering the particulars of Active Galactic Nuclei, the pysical processes and models that are believed to play an important …
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Search for gamma-ray emission from bow shocks of runaway stars
The mystery of the origin of cosmic rays has been tackled for more than hundred years and is still not solved. Cosmic rays are detected with energies spanning more than 10 orders of magnitude and reaching energies up to ~10²¹ eV, far higher than any man-made accelerator can reach. Different …
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A hybrid analysis approach to the high energy stereoscopic system phase II mono-analysis
The High Energy Stereoscopic System (H.E.S.S.) is an array of imaging atmospheric Cherenkov telescopes located in the Khomas highlands of Namibia. Their primary purpose is to detect Cherenkov light (CL) produced by particles in extensive air showers which are produced by incident high energy …
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Multi-messenger constraints and pressure from dark matter annihilation into electron-positron pairs
Despite striking evidence for the existence of dark matter from astrophysical observations, dark matter has still escaped any direct or indirect detection until today. Therefore a proof for its existence and the revelation of its nature belongs to one of the most intriguing challenges of nowadays …
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Physics from Time Variability of the VHE Blazar PKS 2155-304
Blazars are the principal extragalactic sources of very high energy gamma-ray emission in the Universe. These objects constitute a sub-class of Active Galactic Nuclei whose emission is dominated by Doppler boosted non-thermal radiation from plasma outflowing at relativistic speeds from the central …
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Towards Gamma-Ray Telescopes in Australia
Recent decades have seen the rise of the field of gamma-ray astronomy, probing the most extreme environments in our Universe. The upcoming Cherenkov Telescope Array Observatory (CTAO), alongside H.E.S.S. in Namibia, are Imaging Air Cherenkov Telescopes (IACTs) that will cover roughly two thirds of …
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Supernovae as gamma ray emitters from the MeV to the TeV
"Gamma rays offer unique probes of supernovae as cosmic-ray accelerators and as nucleosynthesis sites. My thesis work focuses on how to explore these two aspects of supernovae. (1) Both starburst galaxies and ultra luminous infrared galaxies are new gamma-ray source classes discovered by Fermi and …
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Pulsar wind nebulae at high energies
Pulsar wind nebulae (PWNe) are the most abundant TeV gamma-ray emitters in the Milky Way. The radiative emission of these objects is powered by fast-rotating pulsars, which donate parts of their rotational energy into winds of relativistic particles. This thesis presents an in-depth study of the …