Cosmic Illuminations

Saundra Myers

The answer to a 100 year-old mystery could lie in a flash from space.

ISU professors of physics and astronomy are among researchers from nine universities working on the most sensitive, high-energy gamma ray observatory in the world.

The VERITAS — Very Energetic Radiation Imaging Telescope Array System — is being built in Horseshoe Canyon at Kitt Peak National Observatory in rural Arizona.

Frank Krennrich, associate professor of physics and astronomy; Martin Pohl, assistant professor of physics and astronomy, and David Carter-Lewis, professor of physics and astronomy, along with postdoctoral and graduate students, will lend their efforts to the project.

VERITAS — which means “truth” in Latin — is an array of four telescopes. The ISU group has built a prototype of the telescopes that will be built in Arizona and will build the focal plane for the four telescopes, Krennrich said.

The construct will be an array of four optical reflectors 12 meters in diameter with ultra-fast cameras, which together will form one of the most sensitive high-energy gamma-ray observatories in the world.

Each of the four telescopes will have 350 mirror facets creating a 12-meter aperture, and each will be equipped with a 499-pixel camera, according to a statement from the VERITAS home page, http://veritas.sao.arizona.edu.

The array is being built to study gamma rays, which are waves of light occurring at the highest energy of the electromagnetic spectrum, Carter-Lewis said.

The array’s cameras will provide little snapshots of these rays, which appear as bursts of blue light that last about one-billionth of a second, Krennrich said.

The cameras will capture the highest energies that have been seen from cosmic objects, Carter-Lewis said.

He said one of the goals of the array is to better understand how the laws of nature work in the universe by exploring electromagnetic fields that have not been explored before.

Krennrich said the rays are produced by cosmic events in space, such as black holes and supernovae, and are generally produced in the hottest regions of the universe.

Pohl said gamma rays will be the most useful in discovering why the universe is the way it is because of the limitation of radio and X-rays, creating the need for a new perspective through gamma rays.

“We have to find out what is responsible for producing them,” Pohl said.

“This research will open doors for understanding how phenomena occur.”

One goal of the project is for the telescope to reveal how radiation sources operate and form, Pohl said.

Michael Daniel, postdoctoral research student in physics and astronomy, said finding the source of gamma rays is a first step.

“Gamma rays can be traced back to a source, then they can figure out where other elements in the environment come from,” he said.

Daniel said astronomers will be able to study star formation rates and better understand the evolution of the universe.

“It’s a cosmic laboratory,” Daniel said.