Indirect Searches for Galactic Dark Matter with IceCube-DeepCore and PINGU

Abstract: The cubic-kilometer sized IceCube neutrino observatory is burieddeep in the glacial ice at the Earth’s South Pole. Its low-energyextension array DeepCore enables physicists to search indirectlyfor light Dark Matter (DM) particles with masses as low as tensof GeV/c2 situated within our home galaxy, the Milky Way. GeVneutrinos could be produced through DM particle annihilations,propagating to the Earth where they could be detected by IceCube.This licentiate thesis presents a search for Weakly Interacting Mas-sive Particles (WIMPs) with masses as low as 30 GeV/c2 in theGalactic center (GC) using the 79-string configuration of the IceCubeneutrino detector. Data from 319.7 live-days have been analyzedusing a cut-and-count analysis approach, and found to be consistentwith the background-only hypothesis with expected backgroundfrom atmospheric muons and neutrinos. Thus, upper limits wereset on the velocity averaged DM annihilation cross-section.The Precision IceCube Next Generation Upgrade (PINGU) as apossible future neutrino detector within DeepCore would reducethe neutrino energy detection threshold to a few GeV. In additionto the data analysis with DeepCore, a sensitivity study has beenconducted to investigate the performance of PINGU for indirectDM searches in the GC and the Sun. In the Sun WIMPs could begravitationally captured through elastic scattering off nucleons. Inthis thesis, we derive PINGU sensitivities for the velocity averagedDM annihilation cross-section of WIMPs in the GC, and for theSpin-Dependent (SD) and Spin-Independent (SI) WIMP-protonscattering cross-sections, under the assumption of thermodynamicequilibrium between the WIMP capturing and annihilation rate inthe Sun.