APS Public Comment on NSF South Pole Station Master Plan

RE: Draft South Pole Station Master Plan

Michael Gencarelli
Office of Polar Programs
National Science Foundation
2415 Eisenhower Avenue
Alexandria, VA 22314

Dear Mr. Gencarelli,

As President of the American Physical Society (APS), I am writing along with the leadership of the U.S. high-energy physics users’ organizations of Fermilab, SLAC, and the Large Hadron Collider, on behalf of the physics community to comment on the draft South Pole Station Master Plan. We strongly endorse efforts to recapitalize the infrastructure at the NSF Amundsen-Scott South Pole Station and urge that these vital activities be undertaken in a manner that allows for the Cosmic Microwave Background Stage Four (CMB-S4) project and upgrades to the IceCube experiment to continue, while minimizing delays to the extent feasibly possible. We are particularly concerned with the recently announced decision to not allow the CMB-S4 project to progress to the design stage “in its current form.” The current recapitalization plan provides little detail about what scientists can expect for the future of physics at the Pole. The safety of the scientists and support staff in Antarctica is paramount, so we hope recapitalization can be carried out in a way that prioritizes safety while also avoiding the loss of nearly a decade of scientific progress.

The 2023 Particle Physics Project Prioritization Panel (P5) report, Exploring the Quantum Universe: Pathways to Innovation and Discovery in Particle Physics, is unequivocal about the importance of the South Pole for science: "Maintaining the capabilities of NSF’s infrastructure at the South Pole, focused on enabling future world-leading scientific discoveries, is essential." Both the P5 report and the National Academy of Sciences decadal survey, Pathways to Discovery in Astronomy and Astrophysics for the 2020s, emphasize the importance of the South Pole for CMB-S4 and IceCube-Gen2. Additionally, CMB-S4 is the highest priority major new initiative recommended by P5 during the 2025-35 timeframe.

Cosmic Microwave Background (CMB) measurements explore physics, cosmology, and astrophysics from the early to the late-time universe, providing a path to probing physics at energy scales and early times far beyond the capabilities of terrestrial accelerators. The combination of high altitude and extremely low humidity with little diurnal variation at the South Pole results in uniquely stable and transmissive atmospheric conditions for measurements of the CMB. The unique advantages of the South Pole site for CMB science led to prioritization of a ‘next-generation cosmic microwave background program’ as one of three strategic focus areas across all of Antarctic scientific research in the 2015 NAS report “A Strategic Vision for NSF Investments in Antarctic and Southern Ocean Research.” These advantages led CMB-S4 to propose an ultradeep survey from the South Pole as the optimal experimental configuration to make a transformational measurement of the CMB.

In addition to the CMB studies, the South Pole is also critical for furthering our understanding of neutrinos. The IceCube Neutrino Observatory deploys detectors into the ice to detect the neutrinos that originate in high-energy cosmic accelerators, thereby opening a new window into the high-energy universe. IceCube’s study of cosmic neutrino events is also complementary to terrestrial neutrino experiments, further enabling studies of fundamental neutrino properties. The ongoing IceCube Upgrade will increase the observatories’ sensitivity to low-energy neutrinos, allowing for a uniquely sensitive measurement of neutrino properties. IceCube-Gen2 will boost the sensitivity to cosmic neutrinos by an order of magnitude and increase its energy range by three orders of magnitude, probing the nature of the highest energy particles observed from the Universe.

CMB and neutrino experiments at the South Pole perform many compelling explorations of physics and astronomy beyond those described above. The data collected is used to study everything from the nature of dark energy to the properties of cosmic rays and neutrinos to delving into the mystery of dark matter. These experiments and data sets support a vibrant scientific community and provide important training and development opportunities for the next generation of scientists and engineers. Hundreds of students and postdoctoral scholars are active participants and leaders in the current experiments, making the South Pole Station an essential facility for building the talented STEM workforce necessary for the US to maintain its leadership in science, technology, and innovation.

We fully support the urgently needed recapitalization of the NSF Amundsen-Scott South Pole Station. Robust infrastructure including bedspace, cargo transport, and power generation should be supported at levels that enable maintenance of existing equipment, and construction of new experiments. However, it is vital that South Pole infrastructure recapitalization occur in a manner that enables future scientific investigations there, especially CMB-S4 and IceCube-Gen2, to continue with minimal delay, and which minimizes the disruption to the careers of the talented young scientists who drive these projects forward.

We thank you for your consideration of our input.

Sincerely,

Young-Kee Kim
President, American Physical Society

Also endorsed by:

• André de Gouvêa, Northwestern University, APS Division of Particles and Fields (DPF) Chair
• R. Sekhar Chivukula, UC San Diego, DPF Past Chair
• Heidi Schellman, Oregon State University, DPF Chair Elect
• Sarah Eno, University of Maryland, DPF Vice Chair
• Harvey Newman, Caltech, US LHC Users Executive Committee Chair
• Caterina Vernieri, SLAC, SLAC Users Organization Chair
• Jane Nachtman, University of Iowa, Fermilab Users Executive Committee Chair

CC:

• Jean Cottam Allen, Acting Director, NSF Office of Polar Programs
• Stephanie Short, Section Head, Antarctic Infrastructure and Logistics, NSF Office of Polar Programs
• Sarah Ruth, Acting Section Head, Antarctic Sciences, NSF Office of Polar Programs
• Harriet Kung, Acting Director, DOE Office of Science
• Alexandra Isern, NSF Assistant Director for Geosciences
• Denise Caldwell, Acting Assistant Director, NSF Division of Mathematical and Physical Sciences
• Regina Rameika, Associate Director, DOE Office of High Energy Physics,
• Saul Gonzalez, Division Director, NSF Physics Division