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Programmatics and Schedule V.1 Current Organization 45 V.2 Program Risks and Risk Mitigation 46 V.3 Overall schedule 48 V.4 Key Phase Duration Schedule 50 V.5 Key Event Dates Table 50 V.6 Schedule Charts 51 VI. Cost Section 53 VII. Changes since previous NRC recommendation 70 ! ! ii !"#$%&'(#)*%++,-.! The Square Kilometre Array (SKA) is a revolutionary telescope program that will address a broad range of key science areas in galaxy evolution and cosmology, fundamental physics, and astrobiology. It will also be a superb discovery instrument. The key science goals of the SKA are in place and a well-structured, global technology development program funded at substantial levels is under way. While construction is not funding-ready in 2010, previous and ongoing technology development and cost estimates will lead to technology choices and definitive costings early in the decade and construction proposals for phased deployment on that time scale. These efforts are matched by planning efforts for governance and funding of the project that also are organized by the SPDO (SKA Program Development Office in Manchester, UK). The emphasis of the activity described here is on the mid-frequency array (SKA-mid) because the science goals are timely and the world-wide community is working toward bringing the technical readiness level to that needed for construction by the middle of next decade. Phase 1 comprising low-and-mid frequency arrays will be funding-ready in ~2013 and Phase 2 to complete the array is planned to begin in ~2017. The SKA is presented to Astro2010 as warranting high priority in 2010 on the basis of the science case, the level of global interest and commitment at both of the scientific and governmental levels, the comprehensive international technology development program now in place, and the existence of a well managed international SKA organization to execute the program. It is recognized that funding decisions will depend on the delivery of technology-ready, risk-mitigated proposals along with successful completion of milestones. The submission here includes indicative technologies, costs, and timescales. These will be refined by the SPDO using input from both the international scientific community (via the SKA Science and Engineering Committee, SSEC) and funding agencies (via the Agencies SKA Group) as the SKA program progresses. The SKA presently involves 55 institutions in 19 countries, with the U.S. as a one-third partner. Activities within the U.S. are organized through the U.S. SKA Consortium that includes 11 organizations, including universities, laboratories, and the two national radio observatories (NAIC and NRAO). The Consortium is conducting an SKA Technology Development Project, funded by the NSF in accordance with the last decadal-survey recommendation for the SKA, which contributes key expertise and technology to the global design effort. The baseline design for "#$%&'(! )*&+,'-.-! /000! 12%&! reflectors separated by up to a few thousand kilometers. Signal analysis will provide the unprecedented sensitivity, survey speed, and resolution needed for the key science. Two viable sites for the SKA core array have been identified (Western Australia and South Africa), on which precursor arrays will further develop some of the technologies needed for the SKA. Project milestones over the next few years include site selection targeted for 2012, technology selection, and critical design reviews that will lead to the first phase of construction in ~2015. The anticipated 1/3 contribution of the U.S. is (2009 dollars) ~$725M for construction, $65M/yr for operations, and $10M/yr for programmatic support of U.S. scientists, including a U.S. based SKA Science Center. The draft spending profile for the U.S. starts at about $5M/yr in 2012 and 2013, reaches about $100M/yr during peak construction starting late in the decade and continues near this level for full SKA operations starting in the following decade. 1 .
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