"Jim is a constant professional," a source tells PEOPLE about the funnyman, who shot a promo for Idol Gives Back

By Oliver Jones
Updated April 08, 2010 05:30 PM
Francois G. Durand/WireIma

Jim Carrey isn’t crying over his recent breakup with Jenny McCarthy – at least not publicly.

Hours after announcing his split Tuesday, Carrey was back to work in Los Angeles, filming a promo for Idol Gives BackAmerican Idol‘s annual star-studded charity special.

“You would never have known that [the breakup] had just happened,” says a source. “Jim is a constant professional.”

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Carrey, 48, who filmed the spots in an adjacent studio to where the live American Idol telecast was taking place, was joined by fellow funnymen Russell Brand and Jonah Hill – and the three were in high spirits.

“Jim was loose and relaxed,” the source says. “It was a lot of fun.”

Idol Gives Back will air on April 21.