move forward faster than a U.S. facility and its experimental program can be built? In general, that appears not to be the case, although important exceptions exist. Megaton-scale detectors are long-term projects at an early stage. Since long-baseline neutrino physics is an objective, it is desirable to know more about the neutrino mixing parameters before committing to a design. That may take several years. Of the five ton-scale double beta decay experiments proposed, one is committed to Gran Sasso, two are sufficiently advanced that underground sites will be needed soon, and the other two are in the R&D stage. The low-energy solar neutrino experiments that will follow Borexino and KamLAND are also still in the R&D stage. Large dark-matter detectors are under construction now and can be sited at a number of locations.

In principle any of the intended experiments can be carried out at an existing site somewhere. The added value of a dedicated U.S. deep underground laboratory derives from such factors as priority use for science rather than commercial mining, freedom of access, expandability, common use of infrastructure to support many experiments, and the opportunity for the United States to retain a position of equity and leadership in a major worldwide scientific endeavor.



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