Royalty and diplomats, scientists and business leaders began gathering in the capitals of Sweden and Norway on Tuesday for twin ceremonies honoring the year's Nobel Prize (search) winners, including six Americans.

Iranian human rights activist Shirin Ebadi (search) will become the first Muslim woman to receive the Peace Prize on Wednesday for her work fighting for democracy and the rights of women and children. She will accept a gold medal, a diploma and a $1.4 million award at a ceremony at city hall in Oslo, Norway.

The other 10 Nobel winners — for medicine, physics, chemistry, literature and economics — will receive their awards in Stockholm, Sweden.

The awards ceremony at Stockholm's concert hall was to be followed by a banquet a few blocks away at City Hall.

More than 1,300 guests, including the laureates' families, Sweden's royal family, government officials, ambassadors, scientists and business leaders, were invited to the Stockholm dinner, which was to be broadcast live on Swedish television.

Hundreds of other dignitaries, including the Norwegian royal family, were expected at the peace prize ceremony in Oslo.

J.M. Coetzee (search), 63, was to receive the literature prize, the second South African to pick up the award after Nadine Gordimer in 1991.

American Paul C. Lauterbur and Briton Sir Peter Mansfield were selected for the Nobel Prize in medicine or physiology for discoveries leading to magnetic resonance imaging, or MRI, the body-scanning technique that has revolutionized the detection of disease.

The physics prize went to Alexei A. Abrikosov, of the United States and Russia, Anthony J. Leggett, of the United States and Britain, and Russia's Vitaly L. Ginzburg, for their work concerning two phenomena called superconductivity and superfluidity.

Americans Peter Agre and Roderick MacKinnon won the chemistry prize for their studies of tiny transportation tunnels in human cell walls, work that could lead to greater understanding of diseases of the heart, kidneys, muscles and nervous system.

American Robert F. Engle and Briton Clive W.J. Granger shared the Nobel Memorial Prize in economics for developing statistical tools that have improved the forecasting of economic growth, interest rates and stock prices.

The economics prize was introduced in 1968 and is funded by Sweden's central bank. The other awards are funded by the Nobel Foundation.

The Nobel Prizes are usually announced in October and are handed out every year on Dec. 10, the anniversary of the 1896 death of Nobel, a Swedish industrialist and the inventor of dynamite. The first awards ceremony took place in 1901. Each prize carries a cash award of $1.4 million.