First Measurement of Electron Neutrino Appearance in NOvA

Journal Article · Sat Apr 16 00:00:00 EDT 2016 · Physical Review Letters

DOI:https://doi.org/10.1103/PhysRevLett.116.151806· OSTI ID:1244432

Adamson, P. ^[1]

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1. et al.

We report results from the first search for $$\nu_\mu\to\nu_e$$ transitions by the NOvA experiment. In an exposure equivalent to $$2.74\times10^{20}$$ protons-on-target in the upgraded NuMI beam at Fermilab, we observe 6 events in the Far Detector, compared to a background expectation of $$0.99\pm0.11$$ (syst.) events based on the Near Detector measurement. A secondary analysis observes 11 events with a background of $$1.07\pm0.14$$ (syst.). The $$3.3\sigma$$ excess of events observed in the primary analysis disfavors $$0.1\pi < \delta_{CP} < 0.5\pi$$ in the inverted mass hierarchy at the 90% C.L.

• Research Organization: Fermi National Accelerator Laboratory (FNAL), Batavia, IL (United States); Argonne National Laboratory (ANL), Argonne, IL (United States)
• Sponsoring Organization: USDOE Office of Science (SC), High Energy Physics (HEP)
• Contributing Organization: NOvA
• Grant/Contract Number: AC02-07CH11359
• OSTI ID: 1244432
• Alternate ID(s): OSTI ID: 1247250
• Report Number(s): FERMILAB-PUB-15-262-ND; arXiv:1601.05022; PRLTAO; oai:inspirehep.net:1415951
• Journal Information: Physical Review Letters, Vol. 116, Issue 15; ISSN 0031-9007
• Publisher: American Physical Society (APS)
• Country of Publication: United States
• Language: English

Related Subjects

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