TED KENNEDY by Andy Warhol, Screenprint with diamond dust on board, 1980. Courtesy of the National Portrait Gallery, Smithsonian Institution, Copyright Andy Warhol Foundation for the Visual Arts / ARS, New York When the National Portrait Gallery opened at 11:30 this morning, visitors were able to view the recently installed Andy Warhol portrait of the late Sen. Edward Kennedy in the first-floor gallery space marked “In Memoriam.” The space was designated in June as…