There are three primary ways that naturally occurring radioactive isotopes decay: 1  Alpha particle emission. 2  Beta particle emission. 3  Gamma radiation emission.
President condemns Ankara attacks. The current migration crisis is a problem of the entire EU and not of a particular country, Polish President Andrzej Duda said after the end of the Visegrad Group two-day summit in Balatonfuered, Hungary, on Friday.
A portrait of President Lech Kaczynski of Poland lay among a sea of candles and flowers outside the Presidential Palace in Warsaw. Credit Sean Gallup/Getty Images. This article was reported by Nicholas Kulish, Ellen Barry and Michal Piotrowski, and written by Ms. Barry.