This proposal seeks funding to enhance the capability of IceTop (a surface array of detectors complementing the IceCube Neutrino Observatory built at the South Pole Station) to determine element composition of solar energetic particles in the energy range 1-10 GeV. This will be accomplished by recycling components of the former South Pole neutron monitor to construct an enhanced suite of new detectors whose response functions (primarily due to hadrons) have a different dependence on energy and element composition from those of the IceTop detectors - primarily due to photons and leptons. The proposed project will advance understanding of the acceleration and transport of solar energetic particles with the specific focus areas of the research in the following: (a) deploying an instrument with unique sensitivity to the relative abundance of protons and helium nuclei in solar flare-related particle events at energies above 1 GeV; (b) determining helium abundance for about ten Ground Level Enhancements (GLE) events expected to occur during the project's lifetime through 2014; and (c) putting this information into the context of data on solar energetic particles at lower energy and other observations (optical, radio, X-ray, etc) of these flares. The project will provide data relevant to important societal issues such as space weather studies and enhance the usefulness of data from other instruments.
