We report a fuel-dependent reactor electron antineutrino (νe) yield using six 2.8 GW th reactors in the Hanbit nuclear power plant complex, Yonggwang, Korea. The analysis uses 850 666 νe candidate events with a background fraction of 2.0 % acquired through inverse beta decay (IBD) interactions in the near detector for 1807.9 live days from August 2011 to February 2018. Based on multiple fuel cycles, we observe a fuel 235 U dependent variation of measured IBD yields with a slope of (1.51 ± 0.23) × 10 −43 cm 2 /fission and measure a total average IBD yield of (5.84 ± 0.13) × 10 −43 cm 2 /fission. The hypothesis of no fuel-dependent IBD yield is ruled out at 6.6 σ. The observed IBD yield variation over 235 U isotope fraction does not show significant deviation from the Huber-Mueller (HM) prediction at 1.3 σ. The measured fuel-dependent variation determines IBD yields of (6.15 ± 0.19) × 10 −43 cm 2 /fission and (4.18 ± 0.26) × 10 −43 cm 2 /fission for two dominant fuel isotopes 235 U and 239 Pu, respectively. The measured IBD yield per 235 U fission shows the largest deficit relative to the HM prediction. Reevaluation of the 235 U IBD yield per fission may mostly solve the Reactor Antineutrino Anomaly (RAA) while 239 Pu is not completely ruled out as a possible contributor of the anomaly. We also report a 2.9 σ correlation between the fractional change of the 5 MeV excess and the reactor fuel isotope fraction of 235 U.A definitive measurement of the smallest neutrino mixing angle θ 13 is a tremendous success in neutrino physics during the last decade [1,2]. The measurement has been achieved by comparing the observed ν e fluxes with detectors placed at two different distances from the reactors. As reactor ν e experiments suffer from large reactor related uncertainties of the expected ν e flux and energy spectrum [3][4][5][6][7], identical detector configuration is essential to cancel out the systematic uncertainties. The RAA, ∼6 % deficit of measured ν e flux compared to the HM prediction, is an intriguing mystery in current neutrino physics research and needs to be understood [4][5][6][8][9][10][11]. There have been numerous attempts to explain this anomaly by incorrect inputs to the fission β spectrum conversion, deficiencies in nuclear databases, underestimated uncertainties of reactor ν e model, and the existence of sterile neutrinos [3,[12][13][14][15][16][17][18][19]. Moreover, all of ongoing reactor ν e experiments have observed a 5 MeV excess in the IBD prompt spectrum with respect to the expected one [8,9,20,21]. This suggests that reactor ν e model is not complete at all.In commercial nuclear reactor power plants, almost all (> 99 %)ν e 's are produced through thousands of β-decay branches of fission fragments from 235 U, 239 Pu, 238 U, and 241 Pu. The ν e flux calculation is based on the inversion of spectra of the β-decay electrons of the thermal fissions which were measured in 1980s at ILL [10,11]. The reactor ν e models using these measurements as inputs have large uncertainties [5][6][7]. Therefore, ree...
Low-range expansion of the SCA17 gene is not a rare genetic cause of parkinsonism without ataxia in our population. Reduced penetrance or variable expressivity in low-range expansion might be an explanation for the blurred cutoff point for normal expansion in SCA17.
We conclude that the cortisol response to 1 microg ACTH stimulation was reproducible in both healthy subjects and patients with secondary adrenal insufficiency. In order to assess adrenal function more accurately with the 1 microg ACTH stimulation test, serum cortisol should be measured before and 20 and 30 minutes after ACTH injection.
Spin-phonon coupling mediated by single ion anisotropy was investigated using optical spectroscopy and first-principles calculations in the all-in-all-out pyrochlore magnet Cd_{2}Os_{2}O_{7}. Clear anomalies were observed in both the phonon frequencies and linewidths at the magnetic ordering temperature. The renormalization of the phonon modes was exceptionally large, signifying the presence of an unconventional magnetoelastic term from large spin-orbit coupling. In addition, the relative phonon frequency shifts show a strong correlation with the modulation of noncubic crystal field by the corresponding lattice distortion. Our observation establishes a new type of spin-phonon coupling through single ion anisotropy, a second-order spin-orbit coupling term, in Cd_{2}Os_{2}O_{7}.
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