Chilean authorities decided this week to launch an investigation into the Sept. 23, 1973, death of Communist poet Pablo Neruda, winner of the 1971 Literature Nobel Prize, who is believed to have been poisoned by the military regime of dictator Augusto Pinochet (1973-1990) less than a fortnight after seizing power in a bloody coup d état. At that time, Neruda, 69, was said to be suffering from prostate cancer, but it is believed he was not terminally ill by then.