Progress in Determination of Neutrino Oscillation Parameters

A press release dated 30 March 2006 from the US laboratory, Fermilab, reported the first results from a new neutrino experiment, MINOS (Main Injector Neutrino Oscillation Search). The main injector accelerator at Fermilab produces an intense beam of muon neutrinos and directs them at the MINOS detector in the Soudan mine, at a depth of 716 m, in Minnesota, 732 km away. The MINOS experiment expected to observe 177 ± 11 events, but observed only 92, which is 7.5 \sigma away from 177. The probability that random fluctuations are responsible for this shortfall is only part in $10^{10}$. Thus the MINOS experiment confirmed that there is a shortfall in the number of muon neutrinos if they are detected a long distance away from their point of production