Overview

What makes a star explode and eject its material into space to create planets like earth? What is the mass of the neutrino? And what forces govern the properties of nuclei? Although these questions are very diverse, the research group that I lead uses a common tool to investigate all: charge-exchange reactions. In a nuclear reaction, a projectile nucleus collides with a target nucleus. In a charge-exchange reaction, they exchange a proton for a neutron. These reactions can inform us about electron capture and beta decays that take play important roles in astrophysical phenomena. We are especially interested in supernovae, neutron stars, and processes that create elements in the universe. Another category of processes that we study are those that involve reactions with neutrinos. Such processes also have astrophysical applications. In addition, they help us better understand how these strange particles interact with matter. Finally, we study giant resonances, which are collective oscillations of nuclei that can inform us about bulk properties and equation of state of nuclear matter, which are also important in studying dense stellar phenomena, such as supernovae and neutron stars. To pursue these objectives, we perform experiments with fast beams of rare isotopes and use the S800 spectrometer at the Facility for Rare Isotope Beams (FRIB) at Michigan State University (MSU), in combination with neutron, gamma, and charged-particle detectors. An important aspect of the research performed is to directly couple the experimental results to astrophysical simulations in order to effectively increase our understanding and interpretation of astronomical observations. Our research is supported by the US National Science Foundation.

I also serve as the scientific spokesperson for the FRIB High Rigidity Spectrometer, which will greatly enhance the scientific reach of FRIB. Use the link below to visit the High Rigidity Spectrometer working group website. The High Rigidity Spectrometer is supported by the US Department of Energy, Office of Science, Office of Nuclear Physics.