Download or read book First Observation of the Decay Ks [yields Pi]0[mu]+[mu]− at the NA48 Experiment at CERN. written by Maria Teresa Fonseca Martín and published by . This book was released on 2005 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: A search for the KS → pi 0mu+mu- decay was performed by the NA48/1 Collaboration at the CERN SPS accelerator. Six events were found with a background expectation of 0.22+0.18-0.11 in the data collected in 2002 from the high-intensity K S run. The measured branching ratio is: BR( KS → pi0mu+mu -) = [ 2.9+1.5-1.2 (stat) +/- 0.2(syst)] x 10-9, assuming that only vector currents contribute to the matrix element, and a unit form factor.