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ヤマガタ ジュンコ
YAMAGATA JUNKO
山縣 淳子 所属 京都産業大学 理学部 物理科学科 職種 教授 |
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| 言語種別 | 英語 |
| 発行・発表の年月 | 2012/12 |
| 形態種別 | 研究論文 |
| 査読 | 査読あり |
| 標題 | Branching ratios of mesonic and nonmesonic antikaon absorptions in the nuclear medium |
| 執筆形態 | その他 |
| 掲載誌名 | PHYSICAL REVIEW C |
| 出版社・発行元 | AMER PHYSICAL SOC |
| 巻・号・頁 | 86(6),pp.065205-1-065205-14 |
| 著者・共著者 | Takayasu Sekihara,Junko Yamagata-Sekihara,Daisuke Jido,Yoshiko Kanada-En'yo |
| 概要 | The branching ratios of K- absorption in nuclear matter are theoretically investigated in order to understand the mechanism of K- absorption into nuclei. For this purpose mesonic and nonmesonic absorption potentials are evaluated as functions of nuclear density, the kaon momentum, and energy from one- and two-body K- self-energy, respectively. By using a chiral unitary approach for the s-wave (K) over bar N amplitude we find that both the mesonic and nonmesonic absorption potentials are dominated by the Lambda(1405) contributions. The fraction of the mesonic and nonmesonic absorptions are evaluated to be respectively about 70% and 30% at the saturation density almost independently of the kaon momentum. We also observe different behavior of the branching ratios to pi(+)Sigma(-) and pi(-)Sigma(+) channels in mesonic absorption due to the interference between Lambda(1405) and the I = 1 nonresonant background, which is consistent with experimental results. The nonmesonic absorption ratios [Lambda p]/[Sigma(0)p] and [Lambda n]/[Sigma(0)n] are about unity while [Sigma(+)n]/[Sigma(0)p] and [Sigma(-) p]/[Sigma(0)n] are about 2 due to the Lambda(1405) dominance in absorption. Taking into account the kaon momenta and energies, the absorption potentials become weaker due to the downward shift of the initial K- N two-body energy, but this does not drastirally change the nonmesonic fraction. The Sigma(1385) contribution in the p-wave (K) over bar N amplitude is examined and found to be very small compared to the Lambda(1405) contribution in slow K- absorption. DOI: 10.1103/PhysRevC.86.065205 |
| DOI | 10.1103/PhysRevC.86.065205 |
| ISSN | 2469-9985/2469-9993 |