Fermi National Accelerator Laboratory, Batavia, Illinois 60510, USA.
Phys Rev Lett. 2009 Dec 31;103(26):261802. doi: 10.1103/PhysRevLett.103.261802. Epub 2009 Dec 29.
This Letter reports on a search for nu(mu) --> nu(e) transitions by the MINOS experiment based on a 3.14x10(20) protons-on-target exposure in the Fermilab NuMI beam. We observe 35 events in the Far Detector with a background of 27+/-5(stat)+/-2(syst) events predicted by the measurements in the Near Detector. If interpreted in terms of nu(mu) --> nu(e) oscillations, this 1.5sigma excess of events is consistent with sin2(2theta(13)) comparable to the CHOOZ limit when |Delta m2|=2.43x10(-3) eV2 and sin2(2theta(23))=1.0 are assumed.
这封信件报告了 MINOS 实验通过在费米实验室 NuMI 束中进行 3.14x10(20)个质子靶的暴露，寻找 nu(mu) --> nu(e) 跃迁的结果。我们在远探测器中观察到 35 个事件，而在近探测器的测量中预测的背景为 27+/-5(stat)+/-2(syst) 个事件。如果用 nu(mu) --> nu(e) 振荡来解释，那么这个 1.5sigma 的事件过剩与 sin2(2theta(13)) 是一致的，当 |Delta m2|=2.43x10(-3) eV2 和 sin2(2theta(23))=1.0 时，这与 CHOOZ 极限相当。
