Unraveling mysteries surrounding neutrinos may help us understand Universe better
Recently Department of Energy’s Neutrinos at the Main Injector (NuMI) Off-Axis Electron Neutrino Appearance or (NOvA) Experiment managed to detect neutrinos as well as confirm that they can change form and now researchers at University of Cincinnati believe that unraveling the mysteries surrounding neutrinos could help us understand the Universe better.
Alexandre B. Sousa, University of Cincinnati assistant professor at the McMicken College of Arts and Sciences’ Department of Physics believes that no matter how tiny a mass neutrinos have, they must have an impact on how the universe is evolving.
Sousa says that though finding the mass of neutrinos is an important milestone, it is also critical to understand the mechanism that is responsible for giving mass to these subatomic particles.
NoVA scientists say that their experiments could eventually provide hints about whether neutrinos may have played a role in causing the small matter-antimatter imbalance in the early universe during the big bang, ultimately responsible for us being here to ask the question.
“Depending on their mass, the universe may expand forever, or at some point it may stop expanding altogether and just collapse back,” says Sousa. “So understanding the neutrino flavor change phenomenon will have a great impact.”
Sousa believes that the understanding about the nature of neutrinos and the manner in which they change flavours could have a huge implication on why are we here in the first place and why are we seeing matter, but no antimatter.
“We know neutrinos exist because the first ones were detected in 1956,” says Sousa. “But in the new NOvA experiment, we will detect thousands of these particles. And unlike the electron that will stay an electron until the end of time, we are seeing that neutrinos have these strange properties that enable them to change from one type to another.”
Sousa says he and other scientists are currently studying neutrinos at a fundamental level, but these fundamental understandings often lead to useful applications later. According to Sousa, one direct application of earlier neutrino studies concerns the recent international headlines about the negotiations the U.S. and Iran are trying to secure, which would include essential monitoring of Iran’s production of nuclear energy.
For the uninitiated, neutrinos are said to be the most abundant massive particle in the universe but are still one of the most poorly understood ones. Scientists have been able to find that neutrinos come in three types; however, they don’t know which one is the heaviest and which one is the lightest. This is what researchers intend to do with the NOvA experiment – a litmus test for theories about how the neutrino gets its mass. Researchers will also be trying to see if the neutrino is its own antiparticle.
As for the experiment, the neutrino beam generated at Fermilab passes through an underground near detector where its composition is measured. The beam then travels more than 500 miles straight through the Earth oscillating (or changing types) along the way. About once per second, Fermilab’s accelerator sends trillions of neutrinos to Minnesota, but the elusive neutrinos interact so rarely that only a few will register at the far detector.
When a neutrino bumps into an atom in the NOvA detector, it releases a signature trail of particles and light depending on which type it is: an electron, muon or tau neutrino. The beam originating at Fermilab is made almost entirely of one type — muon neutrinos — and scientists can measure how many of those muon neutrinos disappear over their journey and reappear as electron neutrinos.