The U.S. Securities and Exchange Commission alleges the CEO of Fishers-based Positron Corp. defrauded investors of a hedge fund he operates by secretly investing their money into financially struggling Positron. Patrick G. Rooney, who also is founder and managing partner of Oakbrook, Ill.-based Solaris Management, investment advisers to Solaris Opportunity Fund, “used the fund as Positron’s piggy bank and caused the fund to finance Positron when it had no other sources of funding,” the SEC alleges in a Nov. 18 complaint filed in U.S. District Court for the Northern District of Illinois.