HOLLYWOOD — Seventy-five films are slated to run at the second annual Silverdocs documentary fest.Event, co-presented by the American Film Institute and the Discovery Channel, takes place June 15-20 in Silver Spring, Md., and includes nine U.S. and seven world premieres. Eleven films will compete for a $25,000 prize. Heading the jury is Richard Pena, director of the New York Film Festival and program director for the Film Society of Lincoln Center. Filmmakers presenting new work include George Butler (“Tour of Duty”), Rithy Panh (“The People of Angkor”), Jonathan Stack (“Liberia, an Uncivil War”) and Robert Stone (“Guerrilla: The Taking of Patty Hearst”). Documentarian Barbara Kopple will be honored during the fest’s Charles Guggenheim Symposium.