What will be the next big discovery in particle physics? Perhaps determining the reason that we exist in the universe today, or more specifically why the matter in our universe was not annihilated by an equal amount of antimatter moments after its genesis. In time, the neutrino program that culminates in the Long Baseline Neutrino Experiment (LBNE), which aims to use a megawatt proton beam to send neutrinos through the Earth from Illinois to South Dakota, may provide the answer. The next discovery could be determining with certainty that there are additional undiscovered particles or forces at work in the universe, a possible outcome of the high precision Fermilab Muon g-2 experiment, the ultra-sensitive Muon-to-Electron conversion experiment, or the versatile Belle II experiment. Research in the Intensity Frontier seeks to unearth the new physics that might be at the heart of these big questions by making extremely precise measurements of particle properties and studying some of the rarest particle interactions that the Standard Model predicts:
The very light neutrino particles interact so rarely with other forms of matter that their properties are not well understood, and studying them in more detail may lead to the answers to a number of big questions in particle physics. Quantum mechanics is what allows Intensity Frontier research to answer these questions by making extremely precise measurements of known particles.
Particle interactions have an initial state and a final state, like the starting and ending points of a road trip on a map. It may be possible to take many routes to get from the start to the finish of both a particle interaction and a road trip, but while someone driving a car will choose one specific route to follow on its journey, a particle will explore every possible route simultaneously. The Standard Model of particle physics is like the road map for particles and can be used to predict particle interactions. If a new particle or force exists, it would allow particles to take a route that is missing from the Standard Model map. Making precise measurements of known particles allows scientists to determine whether the Standard Model road map is complete. One interesting aspect of this quantum road map that is quite unlike real roads is that sometimes one route nearly—but not completely—cancels out another, making a particular interaction extremely rare. In this case, new particles or forces could open new routes that ruin the cancellation and lead to significantly enhanced interaction rates. Seeking out these kind of special rare interactions is yet another strategy in the search for something new.
Whether the focus is on precision measurements or the study of rare interactions, Intensity Frontier efforts require the use of powerful particle accelerators and ultra-sensitive detectors to reach their goals. To observe enough rare neutrino interactions to measure their properties well or have a chance to witness an extremely rare Standard Model interaction, an intense beam of particles must provide many chances for the interaction to occur and the detector must be sensitive enough to measure a rare interaction on the first—and perhaps only—opportunity.
For more information…
Intensity Frontier Brochure