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Abstract
As the cosmic radiation is approaching the 100th anniversary of its discovery in 1912, this thesis details three different theoretical approaches to using the IceCube telescope to find the sources of the Galactic cosmic rays, the 'PeVatrons' accelerating cosmic rays up to the 'knee' of the cosmic- ray spectrum.
The photon flux from candidate sources identified by the Milagro gamma-ray detector in a survey of the TeV sky is consistent with the flux expected from a typical cosmic-ray generating supernova remnant interacting with the interstellar medium. We discuss the expected neutrino fluxes from these sources obtained by normalizing to the gamma-ray measurement and the discovery potential for IceCube. We find that the signal is optimally identified by events with energy above 40 TeV and we conclude that evidence for a correlation between the Milagro and IceCube skymaps should be conclusive after several years.
In addition to predicting neutrino fluxes based on previous gamma-ray observations, it may be possible to model high-energy emission from Galactic sources such as pulsars based on a detailed model of how they might accelerate protons. We examine Geminga, the pulsar nearest to Earth, and ask whether a proton beam accelerated by its electric fields might encounter a sufficient target in the photons around the pulsar to produce a beam of neutrinos detectable by IceCube. We conclude that despite tantalizing indications to the contrary, the photons surrounding Geminga are too tenuous and that photopion production will not lead to detectable fluxes of secondary particles.
Finally, we describe in detail an analytic approach to use IceCube as a gamma-ray telescope by determining fluxes of muons from TeV gamma-ray showers. Northern hemisphere gamma-ray observatories such as Milagro and Tibet ASγ have demonstrated the importance of all-sky instruments by discovering previously unidentified sources that may be PeVatrons. We evaluate the potential of IceCube to identify similar sources in the Southern sky and apply this approach to known gamma-ray sources such as supernova remnants. We find that, similar to Milagro, detection is possible in 10 years for sources with fluxes stronger than 10
−11 particles per (TeV cm2 s).
