Measurement of the mass of the electron neutrino using electron capture in 163Ho
Description
An experiment to determine the electron neutrino mass was done by using electron capture in Ho-163. Since the data on the Q-value and half-life of Ho-163, which are closely relevant to the neutrino mass measurement, were contradictory, it was tried to estimate these two quantities from the intensity of M X-ray from Ho-163 and the total number of Ho-163 in the source. The Ho-163 nuclei were produced through the (p, 2n) reaction on Dy-164 by using an AVF cyclotron. The contaminant radioisotopes were completely removed by elaborate chemical separation processes. The total number of Ho-163 atoms was determined by using the PIXE method. The M-capture half-life of Ho-163 was determined from the M X-ray intensity, and was (4.5 +- 1.5) x 104y. This was in good agreement with the CERN's value. By using this value, a useful relation between the Q-value of Ho-163 and the mass of the electron neutrino can be deduced. An upper limit of the mass of the electron neutrino was obtained as 1.25 keV from the Q-value measured by the CERN group. (Kato, T.)
Additional details
Publishing Information
- Imprint Title
- Proceedings of the workshop on 'monopoles and proton decay'
- Imprint Pagination
- 192 p.
- Journal Page Range
- p. 135-149.
- Report number
- KEK--83-12
Conference
- Title
- Workshop on 'monopoles and proton decay'.
- Dates
- 18-20 Oct 1982.
- Place
- Kamioka, Gifu (Japan).
INIS
- Country of Publication
- Japan
- Country of Input or Organization
- Japan
- INIS RN
- 17018397
- Subject category
- S72: PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; S73: NUCLEAR PHYSICS AND RADIATION PHYSICS;
- Resource subtype / Literary indicator
- Conference, Numerical Data
- Descriptors DEI
- ELECTRON NEUTRINOS; EXPERIMENTAL DATA; HALF-LIFE; HOLMIUM 163; KEV RANGE 01-10; LIMITING VALUES; M CAPTURE; PIXE ANALYSIS; Q-VALUE; REST MASS; X-RAY SPECTRA
- Descriptors DEC
- BETA DECAY; BETA DECAY RADIOISOTOPES; CHEMICAL ANALYSIS; DATA; DECAY; ELECTRON CAPTURE DECAY; ELECTRON CAPTURE RADIOISOTOPES; ELEMENTARY PARTICLES; ENERGY; ENERGY RANGE; FERMIONS; HOLMIUM ISOTOPES; INFORMATION; INTERMEDIATE MASS NUCLEI; ISOMERIC TRANSITION ISOTOPES; ISOTOPES; KEV RANGE; LEPTONS; MASS; MASSLESS PARTICLES; NEUTRINOS; NONDESTRUCTIVE ANALYSIS; NUCLEAR DECAY; NUCLEI; NUMERICAL DATA; ODD-EVEN NUCLEI; RADIOISOTOPES; RARE EARTH NUCLEI; SECONDS LIVING RADIOISOTOPES; SPECTRA; X-RAY EMISSION ANALYSIS; YEARS LIVING RADIOISOTOPES