dorsal/arxiv
View SchemaTowards the solution of the $C_{P}/C_{A}$ anomaly in shell-model calculations of muon capture
| Authors | T. Siiskonen, J. Suhonen, M. Hjorth-Jensen |
|---|---|
| Categories | |
| ArXiv ID | nucl-th/9806052 |
| URL | https://arxiv.org/abs/nucl-th/9806052 |
| DOI | 10.1103/PhysRevC.59.R1839 |
| Journal | Phys.Rev. C59 (1999) 1839-1843 |
Abstract
Recently many authors have performed shell-model calculations of nuclear matrix elements determining the rates of the ordinary muon capture in light nuclei. These calculations have employed well-tested effective interactions in large scale shell-model studies. For one of the nuclei of interest, namely $^{28}$Si, there exists recent experimental data which can be used to deduce the value of the ratio $C_{P}/C_{A}$ by using the calculated matrix elements. Surprisingly enough, all the abovementioned shell-model results suggest a very small value ($\simeq 0$) for $C_{P}/C_{A}$, quite far from the PCAC prediction and recent data on muon capture in hydrogen. We show that this rather disturbing anomaly is solved by employing effective transition operators. This finding is also very important in studies of the scalar coupling of the weak charged current of leptons and hadrons.
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"abstract": "Recently many authors have performed shell-model calculations of nuclear\nmatrix elements determining the rates of the ordinary muon capture in light\nnuclei. These calculations have employed well-tested effective interactions in\nlarge scale shell-model studies. For one of the nuclei of interest, namely\n$^{28}$Si, there exists recent experimental data which can be used to deduce\nthe value of the ratio $C_{P}/C_{A}$ by using the calculated matrix elements.\nSurprisingly enough, all the abovementioned shell-model results suggest a very\nsmall value ($\\simeq 0$) for $C_{P}/C_{A}$, quite far from the PCAC prediction\nand recent data on muon capture in hydrogen. We show that this rather\ndisturbing anomaly is solved by employing effective transition operators. This\nfinding is also very important in studies of the scalar coupling of the weak\ncharged current of leptons and hadrons.",
"arxiv_id": "nucl-th/9806052",
"authors": [
"T. Siiskonen",
"J. Suhonen",
"M. Hjorth-Jensen"
],
"categories": [
"nucl-th"
],
"doi": "10.1103/PhysRevC.59.R1839",
"journal_ref": "Phys.Rev. C59 (1999) 1839-1843",
"title": "Towards the solution of the $C_{P}/C_{A}$ anomaly in shell-model calculations of muon capture",
"url": "https://arxiv.org/abs/nucl-th/9806052"
},
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