Search for muon to electron neutrino oscillations

• DOI: 10.1007/bf01957768
• Publication Date: 2005-07-28T15:27:57Z
• Authors: P. Vilain; G. Wilquet; R. Beyer; W. Flegel; T. Mouthuy; H. Øverås; J. Panman; A. Rozanov; K. Winter; G. Zacek; V. Zacek; F. W. Büsser; C. Foos; L. Gerland; T. Layda; F. Niebergall; G. Rädel; P. Stähelin; T. Voss; D. Favart; Gh. Grégoire; E. Knoops; V. Lemaître; P. Gorbunov; E. Grigoriev; V. Khovansky; A. Maslennikov; W. Lippich; A. Nathaniel; A. Staude; J. Vogt; A. G. Cocco; A. Ereditato; G. Fiorillo; F. Marchetti-Stasi; V. Palladino; P. Strolin; A. Capone; D. Pedis; U. Dore; A. Frenkel-Rambaldi; P. F. Loverre; D. Macina; G. Piredda; R. Santacesaria; E. Capua; S. Ricciardi; B. Saitta; B. Akkus; E. Arik; M. Serin-Zeyrek; R. Sever; P. Tolun; M. T. Zeyrek; K. Hiller; R. Nahnhauer; H. E. Roloff
• Keywords: 0103 physical sciences; SCATTERING; SCATTERING; DETECTOR; DETECTOR; 01 natural sciences; 7. Clean energy

A search for νμ → νe and\(\bar \nu _\mu \to \bar \nu _e \) oscillations has been carried out with the CHARM II detector exposed to the CERN wide band neutrino beam. The data were collected over five years, alternating beams mainly composed of muon-neutrinos and muon-antineutrinos. The number of interactions of νe and\(\bar \nu _e \) observed is comparable with the number of events expected from flux calculations. For large squared mass differences the upper limits obtained on the mixing angle aresin22θ < 9.4 · 10−3 for νμ oscillating to νe andsin22θ < 4.8 · 10−3 for\(\bar \nu _\mu \) to\(\bar \nu _e \), at the 90% confidence level. Combining neutrino and antineutrino data the upper limit is 5.6 · 10−3.