Particle Physics Project Prioritization Panel

[2] In 2013, HEPAP was asked to convene a panel (the P5) to evaluate research priorities in the context of anticipated developments in the field globally in the next 20 years.

The report made several recommendations for significant shifts in priority, namely:[4] The panel stressed that the most conservative of the funding scenarios considered would endanger the ability of the U.S. to host a major particle physics project while maintaining the necessary supporting elements.

[7] In 2020, an assessment of progress of the P5-defined program produced by the High Energy Physics Advisory Panel (HEPAP) concluded:[8] "While investments over the past 5 years have focused on project construction, it will be fundamentally important to balance the components of the HEP budget to continue successful execution of the P5 plan.

The HEP research program also needs strong support to fully execute the plan, throughout the construction, operations, and data analysis phases of the experiments, and to lay a foundation for the future."

"[15] Some members of the field have expressed that the pressure to project a unified opinion is stifling debate, with one physicists telling a reporter from Physics Today: "There are big issues people didn’t discuss.

[21] The charge asked P5 to: The priority of projects is being considered within two funding scenarios from the Department of Energy (DOE) and the National Science Foundation (NSF).

Two points made in the report are especially relevant to P5 considerations:[31] 1) The US should prioritize being a "partner of choice" and 2) The US requires a range of project sizes and goals to maintain a healthy "scientific ecosystem".

The primary outcome of the benchmarking report was that "the U.S. is not always viewed as a reliable partner, largely due to unpredictable budgets and inadequate communication, and that shortcomings in domestic HEP programs are jeopardizing U.S.

A second major recommendation of the benchmarking report focused on the need to maintain a program of projects at all scales, from small to large, and that are chosen to specifically enhance areas in which the US technology is lagging, such as in accelerator physics.

In particular, Recommendation 1 stated “As the highest priority independent of the budget scenarios, [funding agencies must] complete construction projects and support operations of ongoing experiments and research to enable maximum science.”[32] This reflects concerns throughout the community of potential abrupt cancellations of ongoing particle physics projects, as flagged by the Benchmarking Panel.

[34] The report also emphasized the importance of the planned expansion of the IceCube neutrino detector in Antarctica, recommending funding for this new project in any budget scenario.

In a recommendation with an unusual level of specifics regarding its implementation, P5 introduced a new program entitled “Advancing Science and Technology through Agile Experiments" (ASTAE).

Only six months after the release of the 2023 P5 report, the first and sixth priority new projects, CMB-S4 and IceCube-Gen2, faced major setbacks from a call by NSF to immediately address the urgent need to update the South Pole Station infrastructure.

[37] Lack of near-term access to infrastructure at the pole led NSF and DOE to cancel the joint-agency CMB-S4 project, despite strong protest from the P5 leadership and appeals from the 500-person, international team.