The Rebel Particle

A sub-atomic particle predicted to exist by physicists has been detected for the first time in a particle accelerator in California - but its properties do not fit with theory. The particle, called Ds (2317), was discovered in the debris of collisions between other sub-atomic particles. But it has baffled and intrigued the 500 physicists working on the project.They think the particle belongs to a family of eight particles known as the charm-strange mesons. Four of them have been found so far, all precisely fulfilling the theorists predictions. But the mass of the newly found Ds particle is significantly smaller than expected, casting doubt on current theories of the nature of matter. The discrepancy means physicists are confronted with a particle they predicted but cannot explain, says the University of Pisas Marcello Giorgi, leader of the international BaBar project that made the discovery. "This has never happened before," he says. "It is very, very exciting".
http://www.newscientist.com/news/news.jsp?id=ns99993687