Research Areas
Electron Accelerator-Based Physics
While proton accelerators provide the most powerful means for exploring the quantum universe, electron accelerators are the most precise. When protons smash together, the most interesting interaction occurs between one constituent from each projectile. All the other components in the collision, however, create a lot of debris that partially obscures the primary collision. When an electron and its opposite, a positron, smash together, there is no debris, creating a very clean collision. The powerful proton collisions provide the big picture. An electron accelerator zooms in to focus on the details.
The BaBar experiment at SLAC’s PEP-II electron-positron collider has provided precision measurements of how matter and antimatter behave differently and why there are so many kinds of particles in the universe. The International Linear Collider, a proposed electron-positron collider or a similar machine, could serve as the next step in discovering new physics. The ILC will allow scientists to home in on the new landscape that the LHC will initially discovery and explore. Together, these unprecedented discovery machines will bring the quantum universe into focus.
Supporting Information
Research Area – Electron-Accelerator Based Research
Where has all the antimatter gone?
Stars are not made of antimatter. People are not made of antimatter. Your chair, desk and computer are all not made of antimatter. Instead, everything we see around us consists of matter. But at the time of the Big Bang, an equal amount of matter and antimatter existed. Where did it all go? Steve Sekula, a postdoctoral researcher at Ohio State University on the BaBar experiment at SLAC, would like to know.
Classified as a B factory, BaBar physicists study the decay of B mesons and B anti-mesons to understand the origin of the broken symmetries in nature, more specifically the breaking of the Charge Parity (CP) symmetry that balances the behavior of matter and antimatter particles. The experiment has already confirmed that the CP symmetry is broken in B decays at a level that is consistent with the Standard Model.
When Sekula joined BaBar as a graduate student in 2000, he focused on the data acquistion system. The experiment accumulated hundreds of gigabytes of data a day, and Sekula helped optimize the system to routinely achieve over 97 percent efficiency. “It put us in the factory mode of a B factory,” says Sekula.
As a postdoc, first at MIT and now at Ohio State, Sekula focuses on analysis. “I look for things that are expected to be really rare in nature,” he says. “If they’re not, it tells us something about the universe.”
Sekula earned his PhD in physics from the University of Wisconsin-Madison and a B.S. from Yale University.
