Supernova neutrino signal in IceCube

IceCube has been completed in December 2010 and now forms a lattice of 5160 photomultiplier tubes covering a volume of ~ km$^3$ in the deep Antarctic ice. Its main design goal is to detect neutrinos with energies greater than 100-GeV. Owing to subfreezing ice temperatures and potassium free glass, the photomultiplier dark noise rates are particularly low. Hence IceCube can also detect MeV neutrinos if they arrive in large numbers by observing a collective rise in all photomultiplier rates on top of the dark noise. Recent work has been focussed on deepening the understanding and subsequently removing several dark noise contributions. IceCubes supernova data aquisition provides a 2 ms time resolution, allowing to to track subtle features in the temporal development of a supernova neutrino burst. Assuming a supernova at the galactic center, the detector's sensitivity compares to a background-free megaton-scale supernova search experiment. The sensitivity decreases to 20 standard deviations at the galactic edge (30 kpc) and 6 standard deviations at the Large Magellanic Cloud (50 kpc). Since 2009, IceCube's supernova alert system has been sending real-time triggers from potential supernovae to the Supernova Early Warning System