Inquirer staff writer Kathleen Brady Shea reports:

A former University of Pennsylvania economics professor who admitted fatally bludgeoning his wife in December 2006 is scheduled to be sentenced this afternoon in Montgomery County Court.

Rafael Robb, 58, of Upper Merion, pleaded guilty a year ago to voluntary manslaughter after facing first- and third-degree murder charges.

At his plea hearing, Robb told Judge Paul W. Tressler that he "just lost it" on Dec. 22, 2006, during an argument about holiday vacation plans with his wife, Ellen, who had been wrapping Christmas gifts. Robb said he had begun flailing at his wife with an exercise bar.

Sentencing guidelines for voluntary manslaughter range from 31/2 to 20 years in prison.

Defense attorney Frank DeSimone has said he will present mitigating circumstances during the sentencing hearing.

The prosecutor, former District Attorney Bruce L. Castor Jr., who has kept the case even though he became a county commissioner in January, has said he will argue for a "substantial" prison term.

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