Alion Science has received a $50 million tack-on to its existing $143 million term loan "B," bringing the total value of the tranche to $193 million. Credit Suisse is leading the deal. The term loan has a tenor of four-and-a-half years and is priced at LIBOR plus 2 1/2%. Moody's Investors Service affirmed its B1 rating of the term loan and downgraded the company's corporate family rating to B2 from B1. Standard & Poor's assigned a rating of B+ to the loan with a recovery rating of 3. An Alion spokesman declined comment.