Two separate university affiliated groups made significant scientific discoveries in the realm of physics this past week.
The Milagro Collaboration and the Advanced Thin Ionization Calorimeter have discovered an excess in cosmic rays in two regions of space closer to Earth than ever has been seen before. Cosmic rays are small quantities of matter that bombard the Earth from anywhere beyond its atmosphere.
The question of where cosmic rays come from has been a mystery to scientists around the world since they were discovered more than 100 years ago.
While some questions undoubtedly linger, physics professor Jordan Goodman said the discoveries announced last week will offer many answers. Goodman said that like most developments in astronomy, there will be little immediate impact. However, the data is one of the first steps to uncovering information about the origin of cosmic rays.
"The progress will be made when the other researchers using different instruments, that we do not have access to, look in this general direction," Goodman said.
Goodman is the principal investigator for Milagro, which is comprised of scientists from 16 institutions from across the United States, including Michigan State University, New York University and University of California at Irvine. The project has taken place in Los Alamos, N.M., since 2000.
Goodman has been going to Los Alamos frequently, bringing faculty and students. He has had undergraduate and graduate students participate in the construction of the project and now actual research.
"This is the kind of research that we in physics get our students actively involved in," Goodman said.
The university first headed the project with help from the National Science Foundation. The name Milagro comes from the movie, The Milagro Beanfield War, that was filmed in 1988 near the site. Milagro also means "miracle" in Spanish.
The project is located in a 60m x 80m x 8m covered pond in the Jemez Mountains near Los Alamos. It was constructed at an altitude of 2,630 meters. The pond is surrounded by an array of 175 instrumented water tanks that span over an area of 40,000 square meters.
Using highly advanced Cherenkov telescopes and satellite experiments, Milagro searches for gamma rays, the most energetic form of light, produced in the hottest regions of the Earth.
The Milagro Collaboration and the ATIC, conceived by university physicist Eun-Suk Seo, reported their findings late last month.
While looking for gamma rays, Goodman said the group stumbled across rare data when they were looking back.
"It is not atypical that interesting discoveries are often made when you are not looking for it," said Goodman, the former physics department chair.
In the Nov. 20 issue of Nature, the ATIC reported an unexpected surplus of cosmic ray electrons in relative proximity. ATIC is an international research project that attempts to solve fundamental questions about the shape of the elemental differential energy spectra.
Normal astronomical telescopes view the universe in visible light, while Milagro views the universe at very high energies. That "light" is about 1 trillion times more energetic than visible light.
"We look at the sky, and we can separate the gamma rays from protons," Goodman said. "Then, we can associate those gamma rays with specific objects in the sky, such as pulsars."
Goodman said that the collaboration has proposed plans to build a follow-up experiment, which will be called the High Altitude Water Cherenkov experiment, at a higher altitude. They have found a location around the Sierra Negra volcano in Mexico to create another telescope.