Program Advisory Committee Evaluates Future Experiments

  • Photo of members of the 47th Program Advisory Committee, along with JLab Deputy Director for Science Bob McKeown.

Jefferson Lab’s 47th Program Advisory Committee met in July to review proposals for future experiments with the Continuous Electron Beam Accelerator Facility

NEWPORT NEWS, VA – Nuclear physicists were feeling the heat during the hottest month of the year, and it wasn’t all due to the weather. During the last week of July, physicists proposing new research for the flagship accelerator on the Department of Energy's Thomas Jefferson National Accelerator Facility campus gathered in Newport News to make the case for their project to a panel of their peers.

Review by the Program Advisory Committee is a major milestone in the life of an experiment. All experiments conducted with the Continuous Electron Beam Accelerator Facility are vetted by the committee, and competition is fierce. New proposals are only

recommended for approval if they represent high quality physics within the range of scientific importance represented by previously approved experiments.

This year, five collaborations proposed new experiments for CEBAF. Each collaboration submitted lengthy proposals and were allowed to make presentations to the PAC to bolster their case. The 13 members of the PAC quizzed the presenters about key details of the proposed experiments and then met behind closed doors to discuss the merits and faults of each.

Of the five new proposals submitted, only one new experiment was approved for future running. Two proposals were also conditionally approved, subject to further review by the PAC.

In addition to reviewing new proposals, the PAC also reviews already approved experiments that have come up for jeopardy. These are experiments that have been approved for running for several years but have not yet been scheduled to run. Six experiments were reviewed, and the PAC recommended that all six remain active, with one experiment receiving an upgraded rating.

“It is a pleasure for us to see CEBAF producing high quality, high energy electron beams for nuclear physics research, and the various collaborations delivering results already from the 12 GeV running,” said PAC chair Jim Napolitano. “The PAC encourages all experiments to deliver their results in as timely a fashion as appropriate standards allow.”

Lastly, Napolitano also commented on a GlueX white paper on future physics in Experimental Hall D that had been requested by the PAC in 2018.

“We were not cavalier when we asked for that last summer. We know that we were asking for a lot, but you guys did a tremendous job. That document was really useful for us,” he said. “We now understand the future. We know what the long-term plans look like, and that’s helpful not only to us, but it will be helpful to future PACs.”

The white paper has been posted publicly on the Hall D website.

The full PAC47 Report has also been posted and may be found on the PAC Reports page of the website.

Contact: Kandice Carter, Jefferson Lab Communications Office, 757-269-7263,


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