Neutrino-Induced Upward-going Muons at MACRO

Upward-going muon events in MACRO allow measurement of the __ ux in the range E _ 10to 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 (____ _ cos _ _ _____ agrees withthe no-oscillation model to no better than 0.1%. The data are in signi_cantly greater agreementwith the __ $ __ vacuum oscillation model, with best-_t parameters of sin22_ _ 1:0 and _m2 _2 _ 10_3eV2=c4. The combined probability (total rate and zenith angle distribution) assigned tothe data under this best-_t assumption is 17%. These results are consistent with measurements atSuperkamiokande and Soudan.