Limits on sensitivity of large silicon bolometers for solar neutrino detection

Estimates are given for ultimate limits on background in proposed direct-counting measurements of neutrino scattering from large silicon crystals. Methods of background reduction are discussed. In the best case, the limiting backgrounds due to activities from cosmic-ray spallation of silicon would be less than the expected true event rate for reactor neutrino measurements of coherent neutral-current scattering from silicon nuclei. Considerable reduction of the estimated high-energy backgrounds would be required for a good signal-to-noise ratio in solar neutrino detection.