GENEVA -- The European Organization for Nuclear Research says it has data that could signal the presence of dark matter, an elusive unseen target that physicists believe makes up as much as a quarter of the universe.
Dark matter is mass that scientists cannot detect directly, but whose existence is inferred through its gravitational pull on visible matter, such as planets. Using a collector mounted on the International Space Station for more than a year, scientists at the CERN research institute gathered data on particles, called positrons, that they believe may be expelled when dark matter collides in a burst of energy and is destroyed.
The collector gathered data on 400,000 positrons, the antimatter form of electrons, creating the largest collection of such particles recorded in space, according to a statement Wednesday. The data are consistent with theories on dark matter, and the experiment will confirm in coming months whether the positrons are a signal for dark matter, Geneva-based CERN said.
"It's a confirmation with much better statistical precision of previous results," William Zajc, chairman of Columbia University's physics department in New York City, said in a phone interview. Preliminary data on the issue have been collected from other satellites beginning in 2007, he said.
Physicists are awaiting further analysis from CERN on the number of positrons and electrons to tell whether the results may signal dark matter, Mr. Zajc said.
"Dark matter is one of the most important mysteries of physics today," CERN said, adding that it will take several years to refine its studies.
The search for dark matter is moving ahead on two fronts. Last month, scientists at CERN announced that they have more certainty that a particle they observed last year is a Higgs Boson, a missing link in physics that would help them explain the makeup of universal phenomena, such as dark matter, that telescopes cannot detect.
In that case, the data were gained using the $10.5 billion Large Hadron Collider, a 17-mile-circumference particle accelerator buried on the border of France and Switzerland. CERN has had 10,000 scientists working on the research, in which billions of subatomic particles are hurled at each other at velocities approaching the speed of light.