Related Experiment Video
Updated: Jul 3, 2026

Picometer-Precision Atomic Position Tracking through Electron Microscopy
Published on: July 3, 2021
Precision measurement of neutrino oscillation parameters with KamLAND
1Research Center for Neutrino Science, Tohoku University, Sendai 980-8578, Japan.
Abstract:
The KamLAND experiment has determined a precise value for the neutrino oscillation parameter Deltam21(2) and stringent constraints on theta12. The exposure to nuclear reactor antineutrinos is increased almost fourfold over previous results to 2.44 x 10(32) proton yr due to longer livetime and an enlarged fiducial volume. An undistorted reactor nu[over]e energy spectrum is now rejected at >5sigma. Analysis of the reactor spectrum above the inverse beta decay energy threshold, and including geoneutrinos, gives a best fit at Deltam21(2)=7.58(-0.13)(+0.14)(stat) -0.15+0.15(syst) x 10(-5) eV2 and tan2theta12=0.56(-0.07)+0.10(stat) -0.06+0.10(syst). Local Deltachi2 minima at higher and lower Deltam21(2) are disfavored at >4sigma. Combining with solar neutrino data, we obtain Deltam21(2)=7.59(-0.21)+0.21 x 10(-5) eV2 and tan2theta12=0.47(-0.05)+0.06.
More Related Videos
07:51Measurements of Soil Carbon by Neutron-Gamma Analysis in Static and Scanning Modes
Published on: August 24, 2017
11:27Studying Soft-matter and Biological Systems over a Wide Length-scale from Nanometer and Micrometer Sizes at the Small-angle Neutron Diffractometer KWS-2
Published on: December 8, 2016
Related Concept Videos
Atomic Nuclei: Larmor Precession Frequency
Distance Measurements by Taping
Measurement: Standard Units
Uncertainty in Measurement: Reading Instruments
Oscillations about an Equilibrium Position
Measurement: Derived Units