Dark-matter detector may set new limits on supersymmetry

Nature : The next-generation XENON100 dark-matter search experiment at Gran Sasso underground laboratory in Italy did not see any dark-matter particles during a recent 100-day run, but the data collected may shed new light on fundamental physics, writes Eugenie Samuel Reich for Nature. In a paper published online yesterday, the XENON100 researchers report that they detected three events during last year’s experiment. Although they did not see evidence of dark-matter particles, their results, if confirmed, contradict earlier findings from other experiments, place new limits on how strongly dark matter interacts with ordinary matter, and may help refine the particle-physics theory known as supersymmetry. However, several researchers have expressed skepticism regarding the XENON100 group’s findings. Juan Collar, a University of Chicago cosmologist who works on CoGeNT, said that a lot rests on the calibration of the XENON100 detector, which he will be looking to study in detail. “Previous attempts by the XENON collaboration to calibrate the response of their detector contained traceable mistakes in methodology,” he said.