Neutrino-Induced Upward-going Muons at MACRO
نویسنده
چکیده
Upward-going muon events in MACRO allow measurement of the ux in the range E 10 to 100 GeV. The ratio of total observed to expected events is 0:74 0:036stat 0:046sys 0:13theor, which when combined with the observed zenith angle distribution ( 1:0 cos 0:1) agrees with the no-oscillation model to no better than 0.1%. The data are in signi cantly greater agreement with the $ vacuum oscillation model, with bestt parameters of sin 2 2 1:0 and m 2 10 3 eV=c. The combined probability (total rate and zenith angle distribution) assigned to the data under this bestt assumption is 17%. These results are consistent with measurements at Superkamiokande and Soudan.
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