Britain's Queen Elizabeth II "died peacefully" on Thursday. She was 96.  The news of her death came just hours after the palace announced that the queen's doctors were "concerned" about her health and were keeping her under "medical supervision" at Balmoral Castle, the British royal family's estate in Aberdeenshire, Scotland, where she has been vacationing this summer.  Royal officials confirmed that Britain's new monarch will be known as King Charles III, ending speculation about whether would use another name during his reign.  Tom Rivers has the latest from London.