Scientists at UH help
discover new matter
University of Hawaii-Manoa physicists and international collaborators have discovered a mysterious subatomic particle.
The "mystery meson," tagged X(3872), can't be explained by current theories of energy and matter, indicating it may be new science, the researchers said.
A meson is a particle that consists of a quark -- a basic unit of matter -- and an antiquark, but X(3872) doesn't fit any known quark-antiquark scheme, said Stephen Olsen, UH professor of physics and astronomy.
Olsen and Sookyung Choi, a Gyeongsang University professor in Korea, detected the particle during experiments in an atom smasher at the High Energy Accelerator Research Laboratory in Tsukuba, Japan.
"If you find a new type of matter, it's always very interesting," said Olsen's colleague, UH-Manoa professor Thomas Browder. "It's not going to guarantee lower taxes or cure cancer, but it's certainly something we have a fundamental curiosity about -- the nature of things that make up the universe."
Normally, a quark and antiquark are held together in a meson by a "color force," the strongest force in nature, Olsen said.
"This particle seems to indicate maybe a little of the color force of the mesons leaked out and the two mesons stuck together," he said.
"If this is true, it is a whole new type of interaction, of behavior at a subatomic level," he said. It would be the first example of a type of meson made from four quarks -- two quarks and two antiquarks.
UH-Manoa physicists are part of an international collaboration of researchers from 11 countries that built and operate the Belle Detector -- a complex of highly sensitive radiation detectors inside a large superconducting electromagnet -- to study particles produced at the laboratory in Japan. Olsen and Browder are Belle team leaders.
The X(3872) particle weighs about the same as an atom of helium and exists for only about one-billionth of a trillionth of a second before it decays to more familiar, longer-lived particles, the scientists said. Although short-lived by human standards, the scientists said it's nearly an eternity for a subatomic particle of that weight.