Constellation Energy shares could remain in focus on Monday after surging more than 25% Friday as the energy giant announced that it will acquire rival Calpine in a deal valued at $26.6 billion. Monitor these key chart levels.

Baltimore-based Constellation’s plans to acquire a Houston, Texas,-based natural gas  producer in a $26.6 billion deal will create one of the nation’s biggest energy firms at a time

Constellation Energy Corporation CEG and Calpine Corp. announced that they have entered into a definitive agreement under which CEG will acquire Calpine in a cash and stock transaction valued at an equity purchase price of nearly $16.