Hartree-Fock calculations of the ratio of bound-state to continuum beta decay of /sup 187/Re, the chronometric partner of /sup 187/Os
Since the ..beta.. decay of /sup 187/Re is first-forbidden unique, the ratio rho of bound-state to continuum ..beta.. decay of /sup 187/Re reduces to a problem in atomic physics. A knowledge of rho is required if one is to connect the experimentally determined value of the rate of continuum decay to a value of the half-life T/sub 1/2/ for the ..beta.. decay of /sup 187/Re. The value of T/sub 1/2/ plays a significant role in the use of the geochemically determined ratio of /sup 187/Os to /sup 187/Re in the estimation of the age of our galaxy. Our results for rho, based on the Hartree-Fock-Dirac single-configuration and the multiconfiguration Dirac-Fock approximations strengthen the conclusion of Williams, Fowler, and Koonin (Astrophys. J. 281, 363 (1984)) based on a modified Thomas-Fermi model, that rho is only of the order of 1%. We also include a few values of the rate for a process first considered by Perrone (Ph.D. thesis, Rice University (1971)), the bound-state ..beta.. decay of a bare /sup 187/Re nucleus. (Since the mass of the /sup 187/Re nucleus is less than the sum of the masses of its daughter nucleus /sup 187/Os and of an electron, continuum decay of a bare /sup 187/Re nucleus is forbidden; neutral /sup 187/Re can ..beta.. decay only because of the greater binding energy of the electrons of /sup 187/Os than of /sup 187/Re.)
- Research Organization:
- Department of Physics, New York University, 4 Washington Place, New York, New York 10003
- OSTI ID:
- 6137540
- Journal Information:
- Phys. Rev. A; (United States), Vol. 35:5
- Country of Publication:
- United States
- Language:
- English
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Related Subjects
RHENIUM 187
BETA-MINUS DECAY
AGE ESTIMATION
BOUND STATE
GALACTIC EVOLUTION
HARTREE-FOCK METHOD
LIFETIME
THOMAS-FERMI MODEL
ATOMIC MODELS
BETA DECAY
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
DECAY
HEAVY NUCLEI
ISOTOPES
MATHEMATICAL MODELS
NUCLEI
ODD-EVEN NUCLEI
RADIOISOTOPES
RHENIUM ISOTOPES
STABLE ISOTOPES
YEARS LIVING RADIOISOTOPES
653005* - Nuclear Theory- Radioactive Decay