TY - JOUR
T1 - No 17 keV neutrino
T2 - Admixture < 0.073% (95% C.L.)
AU - Ohshima, T.
AU - Sakamoto, H.
AU - Sato, T.
AU - Shirai, J.
AU - Tsukamoto, T.
AU - Sugaya, Y.
AU - Takahashi, K.
AU - Suzuki, T.
AU - Rosenfeld, C.
AU - Wilson, S.
AU - Ueno, K.
AU - Yonezawa, Y.
AU - Kawakami, H.
AU - Kato, S.
AU - Shibata, S.
AU - Ukai, K.
N1 - Copyright:
Copyright 2015 Elsevier B.V., All rights reserved.
PY - 1993
Y1 - 1993
N2 - To solve the controversial issue concerning the possible existence of a 17 keV neutrino with a 1% admixture in nuclear β decay, we searched directly for any evidence of a production-threshold effect. The Ni63 β spectrum was measured with a magnetic spectrometer, with very high statistics along with a fine energy scan over a narrow energy region around the expected threshold. The obtained mixing strength was |U|2=[-0.011±0.033(stat)±0.030(syst)]%, very consistent with zero, and decisively excluding the existence of a 17 keV neutrino admixing at the 1% level with the electron neutrino. The corresponding upper limit was set at |U|2<0.073% (95% C.L.). A new limit was also obtained for a wider mass range: |U|2<0.15% (95% C.L.) for 10.5 to 25.0 keV neutrinos.
AB - To solve the controversial issue concerning the possible existence of a 17 keV neutrino with a 1% admixture in nuclear β decay, we searched directly for any evidence of a production-threshold effect. The Ni63 β spectrum was measured with a magnetic spectrometer, with very high statistics along with a fine energy scan over a narrow energy region around the expected threshold. The obtained mixing strength was |U|2=[-0.011±0.033(stat)±0.030(syst)]%, very consistent with zero, and decisively excluding the existence of a 17 keV neutrino admixing at the 1% level with the electron neutrino. The corresponding upper limit was set at |U|2<0.073% (95% C.L.). A new limit was also obtained for a wider mass range: |U|2<0.15% (95% C.L.) for 10.5 to 25.0 keV neutrinos.
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U2 - 10.1103/PhysRevD.47.4840
DO - 10.1103/PhysRevD.47.4840
M3 - Article
AN - SCOPUS:0011682197
VL - 47
SP - 4840
EP - 4856
JO - Physical review D: Particles and fields
JF - Physical review D: Particles and fields
SN - 0556-2821
IS - 11
ER -