Research Areas
Non-Accelerator-Based Physics
The field of non-accelerator physics uses naturally occurring particles and phenomena to explore particle and astroparticle physics. Cosmic rays in the earth's atmosphere and neutrinos from the sun, galactic supernovae and terrestrial nuclear reactors serve as some of the non-accelerator-based particle sources used in this area of research.
In the past decade, experiments like these have revealed a universe far stranger than scientists ever imagined. Ordinary matter—everything that makes up the things we are, see and touch—forms only a small fraction of the universe. Instead 96 percent of the universe consists of mysterious substances called dark energy and dark matter. Physicists believe that dark energy results in the accelerated expansion of the universe. While dark matter holds the galaxies together, but it is a form of matter that does not emit light and therefore difficult to detect with ordinary observation methods.
Non-accelerator-based programs are playing an increasingly important role in this area of high energy physics. Research from such projects as Sudbury Neutrino Observatory (SNO) in Canada, the Pierre Auger Observatory in Argentina, and the Super-K observatory in Japan have provided experimental data, new ideas and techniques complementary to those provided by accelerator-based research on the energy frontier.
Supporting Information
Mixing it up at Daya Bay
Physicists classify the neutrino as the most mysterious of particles. They mix. They have mass, even though the Standard Model stipulates that they shouldn't. They hardly leave a trace behind, making them very difficult to detect. Yet neutrinos may explain the disappearance of antimatter in the universe and whether all the forces become one.
Lisa Whitehead, a postdoctoral researcher at Brookhaven National Laboratory, wants to solve these mysteries. She is a member of the Daya Bay collaboration, an experiment now under construction in China. Daya Bay will use a nuclear reactor to search for the neutrino mixing angle known as "theta one three," measuring the strength of mixing between the first and third types of neutrinos. Past neutrino experiments measured two of the three mixing angles, but "theta one three," or θ13, has proven to be the most challenging. Whitehead writes software and analyzes particle simulations to study different aspects of the experiment that will affect how well Daya Bay can measure θ13. "The experiment needs to be very carefully optimized," she says.
Whitehead is also a member of the MINOS collaboration, another experiment at Fermilab studying neutrino oscillations, including searching for θ13. She has a PhD in physics from Stony Brook and a B.S. in physics and math from Vanderbilt University.
