NEW YORK (REUTERS) - Former Federal Reserve chairman Ben Bernanke began his new job at the Brookings Institution on Monday, wasting no time getting back to work just three days after ending his tenure as head of the world's most powerful central bank.

Mr Bernanke, who led the United States (US) central bank in its aggressive efforts to right the economy after the financial crisis and pull it out of the Great Recession, joined the centrist policy think tank in Washington as a distinguished fellow in residence, Brookings said.

He settled into his office in the morning, a spokesman said, and a new colleague saw him in the cafeteria at lunchtime.

Mr Bernanke, appointed by Republican President George W. Bush as Fed chairman in 2006, gavelled his final policy-setting meeting last week, at which the central bank continued its winding down of the controversial and massive bond-buying programme that was Mr Bernanke's signature strategy to jump-start the tepid recovery.

He was succeeded as Fed chairman by Ms Janet Yellen, the former vice-chair who was sworn in on Monday morning.

Brookings is home to a number of other former Fed officials, including Mr Don Kohn, the vice-chair who preceded Yellen. The institution, home also to scholars on a vast range of topics from climate change to refugee resettlement, prides itself as politically non-partisan and having members on the left and right, although some see it as somewhat left of centre.

The former Princeton professor is expected to write a book and has brought along one of his top Fed press deputies, Mr David Skidmore, to help with editing and research. There are no formal restrictions on his speech now that he is in the private sector, though like any other Fed official he is barred from disclosing confidential information.

"I will still pay close attention to what he says and writes, not because I think he'll have some inside edge on what will happen next with Fed policy, but because he is still one of the smartest guys on the planet when it comes to central banking and monetary theory," said Mr Michael Feroli, JP Morgan's chief economist.

According to a Brookings statement, Mr Bernanke will help bring"rigorous analysis to critical questions" at the institution's new Hutchins Center on Fiscal and Monetary Policy, which is named for private equity investor and donor Glenn Hutchins.

Mr Bernanke's last public appearance was Jan 16 at Brookings, where he said the Fed should give the economy the stimulus it needs despite "credible" worries that its massive bond-buying could destabilise the financial system.

Last week, in his final act as chair, Mr Bernanke and fellow policymakers unanimously agreed to trim US$10 billion (S$12.8 billion) more from the quantitative easing programme, which is now running at US$65 billion per month.

SPOTLIGHT WILL FADE

Mr Bernanke bought trillions of dollars of bonds and promised to keep interest rates near zero well into the future as he fought to respond to the 2007-2009 financial crisis and recession, which infected the rest of the developed world and saw the US unemployment rate climb to 10 per cent in 2009.

Mr Bernanke was not available for an interview. The Brookings spokesman did not comment on his compensation, or on what areas he would focus his initial work.

Having warm ties with Ms Yellen and the respect of the remaining Fed policymakers, Mr Bernanke will probably draw economists' and investors' attention for some time.

"Given that he was an integral part of the policy decision making over the past five years... over the next year he will have some value to the market but less so than Ms Yellen, and it will diminish over time," said Mr Millan Mulraine, a researcher at TD Securities in New York.

"I suspect he will probably keep a fairly low profile - he doesn't want to complicate the process for the new chair."

A QUIET PLACE TO WRITE A BOOK

While Bernanke legacy will hinge heavily on whether the Fed's massive balance sheet, at US$4 trillion and counting, sparks inflation or market disruptions in the future, for now he is being praised as the soft-spoken chairman whose unprecedented policy actions helped avert economic calamity.

His decision to move to a think tank contrasts with the job history of his predecessors.

Mr Alan Greenspan, whose tenure at the Fed is now clouded as having sown the seeds of the crisis, has been criticised for cashing in on his experience by consulting for Wall Street. The former chairman founded his own consulting firm shortly after stepping down on Jan 31, 2006, and a year and a half later was lending his expertise to Deutsche Bank.

Seven months after former chair Paul Volcker stepped down in 1987, he became part-owner and chairman of a small New York investment banking firm, Wolfensohn & Co. Mr Volcker also took a professorship post at Princeton University, where he had gone to college.

Brookings, located about 1.6km north of the Fed's headquarters in the US capital, is also home to former Fed vice-chairs Kahn and Alice Rivlin, who are senior fellows at the economic studies programme that Mr Bernanke joins. Former Fed chairman William McChesney Martin was on its board of trustees, and Ms Leal Brainard, who has been nominated to serve on the Fed Board, was a senior fellow there for many years.

Mr David Wessel, a former reporter who is now a director at the Hutchins Center, quipped that Mr Bernanke will not have to sit through any more policy-setting meetings, testify to "an occasionally hostile Congress", or "listen to complaints from emerging market central bankers".

In a note on the Brookings web site, Mr Wessel also said Brookings will help with the book Mr Bernanke plans to write.

TD's Mulraine said he plans to read Mr Bernanke's book, not that it will contain any "salacious details" about the Fed but for the insights it will provide about policymaking.