phd_thesis__alexander_piegsa__german.pdf

IceCube, a neutrino telescope currently under construction at South Pole, will be completed in 2011. It is able to detect galactic core-collapse supernovae with high statistical significance and unsurpassed precision of the neutrino light curve. Such supernovae are accompanied by a massive outbreak of low-energy neutrinos of all flavors. When flying through ice, which forms the detector medium, positrons and electrons are created. The entirety of local Cherenkov light showers produced by these charge particles light up in the entire ice. Despite IceCube's optimization for high-energy particle tracks, a detection is possible due to a collective noise rate increase in all optical modules. The predominant reaction is the inverse beta decay of anti-electron neutrinos, which make up over 90% of the total signal.



This work describes the implementation and operation of the supernova data acquisition software and real-time analysis, which provided the data since August 2007. The measurements of the first two years of data-taking were analyzed and demonstrate an extremely stable behavior of the total detector with an average failure rate of only 0.3% for the light sensors. A simulation of the detector response for two different supernova models yields a range of sight for IceCube under best conditions up to the Large Magellanic Cloud at 51kpc. Unfortunately, the detector is not able to resolve the deleptonization peak because the neutrino flavor oscillations in the star unfavorably modify the neutrino spectra. However, it may establish the inverse mass hierarchy and $\sin^2 2\theta_{13} > 10^{-3}$ model-independently by evaluating the very early signal rise, as long as the distance to the supernova is <=6kpc. The same may be achieved, by evaluating the possible influence of earth matter on the neutrino oscillation when comparing the result to a second neutrino detector measurement.

English details can be found at:

http://butler.physik.uni-mainz.de/I3Wiki/index.php/Supernovae_signatures_in_IceCube

http://butler.physik.uni-mainz.de/I3Wiki/index.php/Qualification_parameters_of_the_IceCube-DOMs

• Die vorwiegende Reaktion ist der inverse Betazerfall der Antielektronneutrinos , welcher u�ber 90 % des gesamten Signals ausmacht.
• Diese Arbeit beschreibt die Implementierung und Funktionsweise der Supernova-Datennahme-Software sowie der Echtzeitanalyse, mit welcher die oben genannte Nachweismethode seit August 2007 realisiert ist.
• Die Messdaten der ersten zwei Jahre wurden ausgewertet und belegen ein extrem stabiles Verhalten des Detektors insgesamt sowie fast aller Lichtsensoren, die eine gemittelte Ausfallquote von lediglich 0,3 % aufweisen.
• Leider ist der Detektor nicht in der Lage, die Deleptonisierungsspitze aufzul�osen, denn Oszillationen der Neutrinoflavour innerhalb des Sterns...