U of M students building small-scale neutrino detector

Christian Kluge
Christian Kluge is a student in aeronautical engineering at the U of M. Kluge is stringing fiber optic lines through a module that will become part of a neutrino detector.
MPR Photo/Tim Post

Solving the unexplained mysteries of the universe may seem like a big goal for a research project, but that's exactly what scientists hope someday comes out of a work University of Minnesota students are doing this summer.

The students are building parts for a neutrino detector in a huge warehouse near the university's Twin Cities campus.

The detector is a smaller version of a six-story-high device that will be placed in an underground lab in northern Minnesota in few years.

Just trying to understand the concept of neutrinos can boggle the mind.

By the way, in the four seconds it takes you to read that, scientists estimate 200 trillion neutrinos passed through your body.

Neutrinos are tiny particles that travel at nearly the speed of light, through you and through the Earth, without stopping. Most neutrinos passing through us come from the sun.

Neutrinos are hard to detect, and scientists don't really know what happens when they interact with one another.

Caitlin Johnson
Caitlin Johnson is a senior physics and astrophysics major at the University of Minnesota. Johnson is helping build a prototype of the U of M's neutrino detector.
MPR Photo/Tim Post

That's why the University of Minnesota is developing a neutrino detector. The $300 million NOvA project should begin operating in an underground lab in northern Minnesota in a few years. The building-sized detector will intercept particles fired through the Earth in a beam from a lab near Chicago.

It will work in conjunction with other particle experiments going on nearby at the Soudan Underground Mine State Park.

Students at the university are constructing a smaller version of the detector. It will be placed closer to the beam to test the technology involved.

In a 100,000-square-foot warehouse near campus, 19-year-old Dylan Skerbitz is cleaning the ends of a white PVC panel the size of a garage door. He's using a corona arc discharge machine, which looks like a high-tech hair dryer spitting out a purple flame.

"It creates an electrical spark, and it burns off any excess dust or particles so glue will connect better with this," he says.

Corona arc discarge
A corona arc discharge machine is used to clean debris from the ends of neutrino detector modules.
MPR Photo/Tim Post

Each one of these PVC panels -- there will be about 500 stacked together in the finished detector -- is made up of rows of tubes. Each of the tubes will be fitted with long strands of fiber optic thread. Those threads will pick up barely detectable flashes of light when neutrinos do a sub-atomic dance through the detector. A computer will record the findings.

Skerbitz, who's a liberal arts student at the university, is here because he wanted an interesting summer job.

"I'm fascinated by it. The theoretical parts that I understand are very interesting to me," he says. "I don't grasp the math obviously. I think it's really a cool thing."

Nearby, Charles White, who just graduated from the university with a degree in engineering, is stringing fiber optic thread into the PVC panels. It's delicate work.

"The fiber is fragile and also expensive," he says.

Full module
Dylan Skerbitz works on one of the modules that will become part of the University of Minnesota's neutrino detector. A prototype will be made up of 500 of these modules; the full-sized detector will contain 14,000.
MPR Photo/Tim Post

Even though White is building what is essentially a physics experiment, he's getting a chance to use his engineering know how. It's not like you can pick up a machine that dispenses fiber optic thread at your local hardware store. They've had to build and maintain this stuff. "So even if the experiment itself isn't per se an engineering problem, we still have to engineer how to construct all this equipment in a manner that works, which has been a challenge honestly," he says.

The pure physics of it all does fit into what university senior Caitlin Johnson is studying. She's majoring in physics and astrophysics. In the future she'll probably work with the type of equipment she's building now.

"It's kind of cool to be on this end of it, seeing how the experiment and the devices used in research experiments are made so it's definitely a different side of things," she says. "So instead of analyzing the data we're actually building the things that take the data."

It could be several years before the University of Minnesota's neutrino detector produces any real data.

But when it does, scientists hope the findings will help them answer some of the big mysteries of the universe, like what really happened in the first moments of the Big Bang, and why there doesn't appear to be an equal amount of matter and anti-matter in the universe.

University of Minnesota physics professor Daniel Cronin-Hennessy says another great reason to study neutrinos is simply because it adds to our base of scientific knowledge.

"I like to think that we should work toward a goal of having people do those things we do as children, which is try to discover the world," he says.

Cronin-Hennessy says whatever findings the university's neutrino detector uncovers will likely give scientists a lot of new concepts to consider in the decades to come.

Your support matters.

You make MPR News possible. Individual donations are behind the clarity in coverage from our reporters across the state, stories that connect us, and conversations that provide perspectives. Help ensure MPR remains a resource that brings Minnesotans together.