The scientific case for a high-rigidity spectrograph at FRIB has been spelled out in the HRS White Paper, submitted as input to the 2014-2015 Nuclear Science Advisory Committee (NSAC) Long Range Plan.

The experimental program with the HRS will address scientific questions related to all four scientific challenges posed in the National Research Council’s Decadal Study Nuclear physics: Exploring the Heart of Matter:

  1. How did visible matter come into being and how does it evolve?;
  2. How does subatomic matter organize itself and what phenomena emerge?;
  3. Are the fundamental interactions that are basic to the structure of matter fully understood?;
  4. How can the knowledge and technological progress provided by nuclear physics best be used to benefit society?

The HRS will be key to experiments covering 13 of 17 benchmark programs for FRIB introduced by the 2007 Nuclear Science Advisory Committee’s Rare Isotope Beams Task Force. The HRS will deliver on the scientific reach and discovery potential of FRIB by enabling experiments with the most exotic beams up to the highest rare-isotope beam energies (~200 MeV/u) available at FRIB. Through precise exit-channel selection, the HRS will also increase the scientific discovery potential from other state-of-the-art and community-priority devices, such as the Gamma-Ray Energy Tracking Array (GRETA) and the Modular Neutron Array (MoNA-LISA), in addition to other ancillary detectors. The scientific opportunities with the HRS are described in more detail in the whitepaper: "HRS – A High Rigidity Spectrometer for FRIB".