dorsal/arxiv
View SchemaSuperallowed Fermi beta decay and Coulomb mixing in nuclei
| Authors | J. C. Hardy, I. S. Towner |
|---|---|
| Categories | |
| ArXiv ID | nucl-th/9812036 |
| URL | https://arxiv.org/abs/nucl-th/9812036 |
| DOI | 10.1063/1.59543 |
| Journal | AIP Conf.Proc.381:129-140,1999 |
Abstract
Superallowed $0^+ \to 0^+$ nuclear beta decay provides a direct measure of the weak vector coupling constant, $\GV$. We survey current world data on the nine accurately determined transitions of this type, which range from the decay of $^{10}$C to that of $^{54}$Co, and demonstrate that the results confirm conservation of the weak vector current (CVC) but differ at the 98% confidence level from the unitarity condition for the Cabibbo-Kobayashi-Maskawa (CKM) matrix. We examine the reliability of the small calculated corrections that have been applied to the data, and conclude that there are no evident defects although the Coulomb correction, $\delta_C$, depends sensitively on nuclear structure and thus needs to be constrained independently. The potential importance of a result in disagreement with unitarity, clearly indicates the need for further work to confirm or deny the discrepancy. We examine the options and recommend priorities for new experiments and improved calculations. Some of the required experiments depend upon the availability of intense radioactive beams. Others are possible with existing facilities.
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"abstract": "Superallowed $0^+ \\to 0^+$ nuclear beta decay provides a direct measure of\nthe weak vector coupling constant, $\\GV$. We survey current world data on the\nnine accurately determined transitions of this type, which range from the decay\nof $^{10}$C to that of $^{54}$Co, and demonstrate that the results confirm\nconservation of the weak vector current (CVC) but differ at the 98% confidence\nlevel from the unitarity condition for the Cabibbo-Kobayashi-Maskawa (CKM)\nmatrix. We examine the reliability of the small calculated corrections that\nhave been applied to the data, and conclude that there are no evident defects\nalthough the Coulomb correction, $\\delta_C$, depends sensitively on nuclear\nstructure and thus needs to be constrained independently. The potential\nimportance of a result in disagreement with unitarity, clearly indicates the\nneed for further work to confirm or deny the discrepancy. We examine the\noptions and recommend priorities for new experiments and improved calculations.\nSome of the required experiments depend upon the availability of intense\nradioactive beams. Others are possible with existing facilities.",
"arxiv_id": "nucl-th/9812036",
"authors": [
"J. C. Hardy",
"I. S. Towner"
],
"categories": [
"nucl-th",
"hep-ph",
"nucl-ex"
],
"doi": "10.1063/1.59543",
"journal_ref": "AIP Conf.Proc.381:129-140,1999",
"title": "Superallowed Fermi beta decay and Coulomb mixing in nuclei",
"url": "https://arxiv.org/abs/nucl-th/9812036"
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