First results from KamLAND: evidence for reactor antineutrino disappearance.
نویسندگان
چکیده
KamLAND has measured the flux of nu;(e)'s from distant nuclear reactors. We find fewer nu;(e) events than expected from standard assumptions about nu;(e) propagation at the 99.95% C.L. In a 162 ton.yr exposure the ratio of the observed inverse beta-decay events to the expected number without nu;(e) disappearance is 0.611+/-0.085(stat)+/-0.041(syst) for nu;(e) energies >3.4 MeV. In the context of two-flavor neutrino oscillations with CPT invariance, all solutions to the solar neutrino problem except for the "large mixing angle" region are excluded.
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ورودعنوان ژورنال:
- Physical review letters
دوره 90 2 شماره
صفحات -
تاریخ انتشار 2003