Page One

Berkeley lab retracts discovery of elements

The Associated Press
Monday July 30, 2001

Physicists at the Lawrence Berkeley National Laboratory are retracting a 1999 claim of having discovered two “superheavy” elements in a fusion of lead and krypton. 

The researchers announced the reversal, possibly the first made by the Berkeley lab, in a formal statement to Physical Review Letters, a scientific journal that carried the original results. 

“The evidence wasn’t there,” Ken Gregorich, a nuclear chemist at the lab and leader of the research group, said. 

In 1999, then-Energy Secretary Bill Richardson called the discovery “stunning.” He said then the findings were of international importance, since, besides team members from Oregon State University and the University of California at Berkeley Chemistry Department, four researchers were German. 

Gregorich had initially called the findings an “unexpected success (that) opens up a whole world of possibilities.” 

But the interpretation of experiments conducted using the lab’s 88-inch cyclotron, a powerful particle accelerator, was flawed. 

The Berkeley team had hoped to briefly fuse krypton and lead. They focused beams of high-energy krypton ions at lead targets, and thought they had produced a fragile element — Element 118, which would have been the heaviest element ever seen in a lab. 

The scientists also believed then that they had made Element 116, a decay product of 118, which would have been another important find. 

However, subsequent independent laboratory studies were not able to reproduce the 1999 findings. The troubled Berkeley team later reviewed their original data using refined computer programs. They found nothing. 

“The truth is we don’t really understand how it happened,” Gregorich said.  

“We’re still working on it.” 

A group of senior lab managers is now being assembled to review the way scientists conduct experiments and handle data at the Berkeley lab, according to Pier Oddone, the Berkeley lab’s deputy director in charge of scientific research. 

Though the error is embarrassing, the Berkeley scientists aren’t the first to have to correct their findings. 

“Things like this happen in science,” said Witold Nazarewicz, a physics professor at the University of Tennessee and an investigator at the Oak Ridge National Laboratory.  

“It’s a sad day. But even though it’s painful . . . this is the way scientists should behave. So at the end of the day there is a mechanism for self-correction.”