Measurements of the solar neutrino spectrum have already yielded unexpected results of fundamental importance and, as these measurements improve, new results promise to be equally revealing. Neutrino oscillations, coupled with the MSW mechanism, are required to explain the observed neutrino fluxes at Earth. This solution allows an interesting region between vacuum- and matter-enhanced oscillations where additional new physics can be probed. Likewise, recent solar abundance measurements have created conflicts between the Standard Solar Model and helioseismology results, which are most sensitively resolved by measurement of the CNO neutrino flux. Significantly, there also remains the question whether the luminosity of the sun, as determined by photons, accurately matches the luminosity as determined by neutrinos. In this case, a direct measurement of the pp neutrinos is also required.
This award will provide funding for this group to continue their participation in the science arena of Borexino in the underground laboratory at Gran Sasso, Italy as the collaboration focuses on measuring the Beryllium-7 neutrino flux. The group actively participated and provided expert manpower to Borexino purification efforts. Results from the first pass of purification have been very successful, and when completed in the coming year, Borexino looks well poised to provide meaningful measurements of the CNO and pep fluxes as well. Future possibilities include measurements of the pp neutrino flux with the LENS experiment.
This award will provide excellent training of, and experience for, the students and postdocs who work in the program as well as potential applications of these technologies outside of the field.
