UM scientists studies fastballs from space

Few people know their heads are hit with the energy of two Nolan Ryan fastballs every second. Fewer still know where that energy comes from, but a University of Montana scientist is trying to find out.

Fred Miller
Montana Kaimin

http://www.kaimin.org/test2.php?ardate=20040219&id=2478

When John Belz, an assistant physics professor, came to Missoula in 2002, he brought with him an international project to study subatomic particles. Subatomic particles are the tiny building blocks of atoms. UM’s Department of Physics and Astronomy joins nine other universities throughout the world — from Utah and New Mexico to as far away as Japan — in developing the new technology to discover what these “fastballs from space” are all about.

The Earth’s atmosphere is bombarded with protons from far-away energy sources, Belz said. The protons are hard to study with satellites in space because they are relatively few and far between, he said. But when they hit the atmosphere they break up into lots of smaller particles that give off flashes of ultraviolet light and spread uniformly over the Earth. The particles are much smaller than baseballs, but at the speed of light (186,000 miles per second) they beat Ryan’s record of almost 100 mph by nearly 7 million times. Belz and his colleagues use a ground observatory in Utah — called the “High Resolution Fly’s Eye” because of its many light detectors — to see the ultraviolet light these particles give off. The detectors can also measure energy and point to where the particles came from.

“What we look for is flashes of light that are produced when very high-energy cosmic rays hit the atmosphere,” Belz said.

This light-scattering phenomenon can be seen on Earth in the form of the Aurora Borealis, or Northern Lights, Belz said, which occur when charged particles from the sun become trapped in the Earth’s magnetic field. But the cosmic rays that Belz’s colleagues study come from energy sources 100,000 to a million times more powerful than an exploding star.

“I study the highest energy,” Belz said.

Because of the direction many of the particles have been seen to come from, it is theorized that Earth is the recipient of energy from radio galaxies, including galaxies 50 million light years away. Radio galaxies have black holes in their centers that rotate very fast, suck in enormous amounts of matter and shoot it out of both ends, Belz said.

In the basement of UM’s Science Complex, Belz showed some equipment he and some of his students are working on building for the Telescope Array in Utah, a project he said would use mirrors and extremely sensitive light detectors to better track the particles.

The project will include 256 small photo tubes to convert light into electrical pulses. It will also have more sensors on the ground.

“It’s very fast flashes and very faint flashes that this is good for seeing,” he said.

The project will cost about $20 million, funded by a $12 million grant from the Japanese government and a $5 million to $6 million U.S. grant he said he hopes will grow to match the Japanese contribution.

Belz has recruited three UM students and one Montana State University graduate student to help him. Daniel Guest, a UM junior in physics, was on hand in the basement lab to explain some of the workings of the equipment. His specialty is building equipment in the lab’s machine shop, he explained.

Belz said the experiments are a good experience for UM students interested in going further with physics and he’s glad to have them to help with the research.

“Myself and some of the students will do what astronomers do and stay up all night,” he said.