Fermilab is asking 100 employees to voluntarily quit as it seeks to cut expenses.
Laboratory director Pier Oddone announced a voluntary severance separation plan to employees Thursday.
Employees have until July 7 to apply and will be notified July 21 or 22 if they have been accepted.
Employees in all departments are eligible.
Applications will be evaluated and eligibility will be determined, in part, by the laboratory's staffing needs, so even if 100 people apply not all 100 people may be accepted, Oddone said.
And if Fermilab doesn't meet its goal of 100, it might lay people off, he said.
Oddone told employees the lab is likely to continue to face tight financial constraints for several years as the federal government decides what to do about large budget deficits. In 2008, the lab had rolling unpaid furloughs for all workers for several months when its budget was cut.
When the Tevatron accelerator shuts down this fall, some workers from that project will be transferred to other projects, Oddone said.
" ... There will still, however, be a mismatch between our current workforce and what is needed for the future program," Oddone wrote in a letter to employees.
Last November, the lab offered separation incentives to 600 employees, hoping 50 would take it. Thirty did.
Fermilab employs 1,926 people full- and part-time. Its highest workforce in the last 20 years was in 1993, when it had 2,314.
Scientists account for nearly 20 percent of its workforce. Technicians and technology specialists amount to about 23 percent, and engineers 12 percent.
The Tevatron particle accelerator has been used for 28 years since the federal lab started operating. It was the most powerful in the world until the Large Hadron Collider went online in September 2008 in Europe. Fermilab officials had hoped to keep the Tevatron running another few years, but were denied.