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12 GeV Upgrade Status

Project Execution (Construction)

DOE - convened Progress Reviews:

Supporting Construction (JLab-convened reviews to date):

Critical Decision Three (CD-3)

The project received CD-3 (Approve Construction Start) on Sept. 15, 2008. Construction funds are requested in the President's Fiscal Year 2009 Budget Request, and project completion is planned for 2015. "Today's approval is truly historic," said Dr. Jehanne Simon-Gillo, acting associate director of DOE's Office of Science for Nuclear Physics. "The 12 GeV CEBAF upgrade will enable scientists to seek answers to some of Nature's most perplexing questions, expand our knowledge of the universe and benefit people around the world. The project also clearly demonstrates our Nation's commitment to remaining in the forefront of scientific exploration and discovery." CD-4 (Approve Start of Operations) is scheduled for 2015.

CD-3 Requirements:

Supporting CD-3 (JLab-convened reviews to date):

Critical Decision Two (CD-2)

The project received CD-2 (Approve Performance Baseline) on Nov. 9, 2007. Dr. Jehanne Simon-Gillo, the acting associate director for the DOE's Office of Science for Nuclear Physics, said the approval "marks a significant achievement for Jefferson Lab." She also added that, "The 12 GeV Upgrade Project will allow nuclear scientists to delve deeply into the heart of the nucleon, and will permit Jefferson Lab to remain a unique international facility for decades." CD-3 (Approve Construction Start) is expected in 2008 and CD-4 (Approve Start of Operations) scheduled for 2015.

12 GeV: Program Advisory Committee (PAC)

PAC 34:

The Jefferson Lab Program Advisory Committee held its 34th meeting Jan. 26 -30, 2009. The Committee reviewed and made recommendations for the 19 proposals and 6 Letters of Intent for experiments with the 12 GeV Upgrade. Of the proposals, nine were approved, five conditionally approved and five deferred or rejected for various reasons. Five of the letters of intent were deemed sufficiently attractive for the team to be encouraged to proceed to develop a proposal.

PAC 34 was the first 12 GeV PAC to consider new initiatives for the 12 GeV era that would go beyond the baseline equipment included explicitly as part of the 12 GeV Upgrade Project.

Among the proposals well received were one to measure the weak coupling of electrons using Møller Scattering and three that will use various configurations of apparatus that is collectively known as the SuperBigBite Spectrometer. Another proposed experiment with major apparatus would more broadly explore parity violation in deep inelastic collisions. The Møller Scattering experiment falls into one of the categories, fundamental symmetries, which was explicitly called out both by NSAC and by the DOE Science Review of the 12 GeV Upgrade as a strength of the 12 GeV project and its planned program.

All 19 experiments considered at this PAC are part of the central mission of JLab physics to illuminate the properties of nucleons and how these are reflected by the flavor, momentum and angular momentum carried by their constituent quarks and gluons.

The PAC grouped these proposals into 4 distinct programs for consideration:

The detailed proposals are available on the JLab website here.

PAC 33:

The meeting of PAC 33 was held Jan. 14 -18, 2008. The PAC reviewed 25 proposals and 1 Letter of Intent. The Committee completed a thorough assessment and ten proposals were approved, nine were conditionally approved, and seven proposals were deferred. PAC 33 represented the last 6 GeV PAC. The demand for beam time was strong, so it was disappointing to learn that the FY08 budget did not significantly increase funding for operations. Given the remarkable number of exceptional quality 6-GeV physics proposals, the lab and DOE/NP are encouraged to develop a plan that will allow as much as possible of the approved 6-GeV program to be completed before its termination for the Upgrade. The detailed proposals are available on the JLab website here.

PAC 32:

The second meeting of the Jefferson Lab PAC that formally considered proposed experiments for the Upgrade (PAC 32) took place from Aug. 6 - 8, 2007. A total of nine proposals and three letters of intent for experiments that will use the base equipment planned for the Upgrade were submitted by JLab users. The PAC recommended approval (or conditional approval) of eight of the proposals. The detailed proposals are available on the JLab website at http://www.jlab.org/exp_prog/proposals/07prop.html. With this review, the decision process necessary to finalize and prioritize the initial science program for the 12 GeV Upgrade is continuing.

PAC 30:

The first meeting of the Jefferson Lab PAC that formally considered proposed experiments for the Upgrade (PAC30) took place from Aug. 21 - 26 , 2006. A total of 22 proposals and eight letters of intent for experiments that will use the base equipment planned for the Upgrade were submitted by JLab users, and the PAC recommended approval (or conditional approval) of 17 of them. The detailed proposals are available on the JLab website at http://www.ilab.orq/exp_proq/proposals/06prop.html. With this review, the decision process necessary to finalize and prioritize the initial science program for the 12 GeV Upgrade got underway.

CD-2 Requirements:

Supporting CD-2:

Critical Decision One (CD-1)

The project received CD-1 (Approve Alternative Selection and Cost Range) in February 2006 with an announcement made on Feb. 22nd by the Secretary of Energy, Samuel W. Bodman, during a visit to Jefferson Lab where it was also announced that President Bush's Fiscal Year 2007 budget request included $7 million for the 12 GeV Upgrade. The Project Engineering and Design (PED) phase is underway.

Group photograph

Supporting CD-1:

CD-1 Requirements:

Science Review of the 12 GeV Upgrade

In support of the review process for the next critical decision, Jefferson Lab and the user community further defined and updated the scientific motivation. The Office of Nuclear Physics conducted a Science Review of the 12 GeV Upgrade in April 2005 using a panel of international experts to assess the major elements of the science program: gluonic excitations, the fundamental structure of hadrons, the physics of nuclei, and fundamental symmetry tests in nuclear physics. The panel concluded that the research is "unique to TJNAF and will not be possible at any other known facility in the foreseeable future", and that "the scientific opportunity afforded by the 12 GeV Upgrade is outstanding, providing the U.S. with unique world-leadership capabilities in studies of QCD and the quark structure of matter." Both the search for exotic mesons and the study of fundamental symmetries were noted as having "discovery potential."

Critical Decision Zero (CD-0)

The Critical Decision process was implemented by the U.S. Department of Energy to ensure that capital projects "are delivered on schedule, within budget, and fully capable of meeting mission performance and environmental, safety, and health standards." It is a five-step approval process that all capital projects, such as the 12 GeV Upgrade, must follow. The 12 GeV CEBAF Upgrade of Jefferson Lab received Critical Decision Zero (CD-0) approval in March 2004. This affirmed that the Department of Energy had approved the mission need of the project which allowed Jefferson Lab scientists to proceed with the conceptual design and to request project funding.