Particle Astrophysics

Particle physics plays an essential role in the broader enterprise of the physical sciences. It inspires U.S. students, attracts talent from around the world, and drives critical intellectual and technological advances in other fields. It is entering an era of unprecedented potential as a result of new discoveries about matter and energy in the Universe. Particle physics addresses fundamental questions in three overlapping domains: the Energy Frontier, the Intensity Frontier and the Cosmic Frontier. The Particle Physics program seeks to explore the fundamental nature of matter, energy, space, and time. It asks such questions as: What are the origins of mass? Can the basic forces of nature be unified? How did the universe begin? How will it evolve in the future? What are dark matter and dark energy? Are there extra dimensions of space-time? Formerly separate questions in cosmology (the universe on the largest scales) and quantum phenomena (the universe on the smallest scales) become connected through our understanding that the early universe can be explored through the techniques of particle physics. At the NSF, particle physics is supported by three programs within the Division of Physics: (1) the Theory program, which includes fundamental research on the forces of nature and the early history of the universe as well as support for the experimental program by providing guidance and analysis for high energy experiments; (2) the Elementary Particle Physics (EPP) program, which supports particle physics at accelerators, and (3) the Particle Astrophysics (PA) program, which supports non-accelerator experiments. The Particle Astrophysics program supports university research in many areas of particle astrophysics, including the study of ultra high energy particles reaching Earth from beyond our atmosphere and experiments or research and design projects for underground facilities. Currently supported activities are: ultra high energy cosmic-ray, gamma-ray and neutrino studies; the study of gamma-ray bursts and solar, underground and reactor neutrino physics; neutrino mass measurements; searches for the direct and indirect detection of Dark Matter; searches for neutrino-less double beta decay; and studies of Dark Energy. It should be noted that proposals that are submitted to the PA program and are requesting in excess of $1,000,000/year may, at the discretion of the Program Officer, be subjected to an additional level of scrutiny in the form of a cost review that would take place before the annual PA panel that meets to discuss all of the submitted proposals.