Ulrich Heintz Brown University

the final LEP result
“the results of the experiment were inconclusive so we had to use statistics...”
from Louis Lyon’s book “statistics for nuclear and particle physicists”
CLs
• small if data agree better with
background only
• large if data agree better with
signal+background
signal can be excluded at 95% CL if CL s < 0.05
exclude m H < 114 GeV
3/24/2011 Ulrich Heintz - Moriond QCD
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