Λ single particle energies
The Λ single-particle energies BΛ of hypernuclei (HN) are calculated microscopically using the Fermi hypernetted chain method to obtain for our ΛN and ΛNN potentials the Λ binding D(ρ) to nuclear matter, and the effective mass m*Λ(ρ) at densities P≤ρ0 (ρ0 is normal nuclear density), and also the cor...
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| Format: | Article |
| Language: | English |
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American Physical Society
1999
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| Online Access: | http://psasir.upm.edu.my/id/eprint/40238/ http://psasir.upm.edu.my/id/eprint/40238/1/%CE%9B%20single%20particle%20energies.pdf |
| _version_ | 1848849369052217344 |
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| author | Usmani, Qamar N. Bodmer, A. R. |
| author_facet | Usmani, Qamar N. Bodmer, A. R. |
| author_sort | Usmani, Qamar N. |
| building | UPM Institutional Repository |
| collection | Online Access |
| description | The Λ single-particle energies BΛ of hypernuclei (HN) are calculated microscopically using the Fermi hypernetted chain method to obtain for our ΛN and ΛNN potentials the Λ binding D(ρ) to nuclear matter, and the effective mass m*Λ(ρ) at densities P≤ρ0 (ρ0 is normal nuclear density), and also the corresponding effective ΛN and ΛNN potentials. The Λ core-nucleus potential UΛ(r) is obtained by suitably folding these into the core density. The Schrödinger equation for UΛ and m*Λ is solved for BΛ. The fringing field (FF) due to the finite range of the effective potentials is theoretically required. We use a dispersive ΛNN potential but also include a phenomenological ρ dependence allowing for less repulsion for ρ<<ρ0, i.e., in the surface. The best fits to the data with a FF give a large ρ dependence, equivalent to an A dependent strength consistent with variational calculations of 5ΛHe, indicating an effective ΛNN dispersive potential increasingly repulsive with A whose likely interpretation is in terms of dispersive plus two-pion-exchange ΛNN potentials. The well depth is 29±1 MeV. The ΛN space-exchange fraction corresponds to m*Λ(ρ)≈0.75-0.80 and a ratio of ρ-to s-state potentials of ≈0.5±0.1. Charge symmetry breaking (CSB) is significant for heavy HN with a large neutron excess; with a FF the strength agrees with that obtained from the A = 4 HN. The fits without FF are excellent but inconsistent with the requirement for a FF, with 5ΛHe, and also with the CSB sign for A = 4. |
| first_indexed | 2025-11-15T09:49:18Z |
| format | Article |
| id | upm-40238 |
| institution | Universiti Putra Malaysia |
| institution_category | Local University |
| language | English |
| last_indexed | 2025-11-15T09:49:18Z |
| publishDate | 1999 |
| publisher | American Physical Society |
| recordtype | eprints |
| repository_type | Digital Repository |
| spelling | upm-402382015-09-14T08:28:53Z http://psasir.upm.edu.my/id/eprint/40238/ Λ single particle energies Usmani, Qamar N. Bodmer, A. R. The Λ single-particle energies BΛ of hypernuclei (HN) are calculated microscopically using the Fermi hypernetted chain method to obtain for our ΛN and ΛNN potentials the Λ binding D(ρ) to nuclear matter, and the effective mass m*Λ(ρ) at densities P≤ρ0 (ρ0 is normal nuclear density), and also the corresponding effective ΛN and ΛNN potentials. The Λ core-nucleus potential UΛ(r) is obtained by suitably folding these into the core density. The Schrödinger equation for UΛ and m*Λ is solved for BΛ. The fringing field (FF) due to the finite range of the effective potentials is theoretically required. We use a dispersive ΛNN potential but also include a phenomenological ρ dependence allowing for less repulsion for ρ<<ρ0, i.e., in the surface. The best fits to the data with a FF give a large ρ dependence, equivalent to an A dependent strength consistent with variational calculations of 5ΛHe, indicating an effective ΛNN dispersive potential increasingly repulsive with A whose likely interpretation is in terms of dispersive plus two-pion-exchange ΛNN potentials. The well depth is 29±1 MeV. The ΛN space-exchange fraction corresponds to m*Λ(ρ)≈0.75-0.80 and a ratio of ρ-to s-state potentials of ≈0.5±0.1. Charge symmetry breaking (CSB) is significant for heavy HN with a large neutron excess; with a FF the strength agrees with that obtained from the A = 4 HN. The fits without FF are excellent but inconsistent with the requirement for a FF, with 5ΛHe, and also with the CSB sign for A = 4. American Physical Society 1999 Article PeerReviewed application/pdf en http://psasir.upm.edu.my/id/eprint/40238/1/%CE%9B%20single%20particle%20energies.pdf Usmani, Qamar N. and Bodmer, A. R. (1999) Λ single particle energies. Physical Review C: Nuclear Physics, 60 (5). art. no. 055215. pp. 1-16. ISSN 0556-2813; ESSN: 1089-490X http://journals.aps.org/prc/abstract/10.1103/PhysRevC.60.055215 10.1103/PhysRevC.60.055215 |
| spellingShingle | Usmani, Qamar N. Bodmer, A. R. Λ single particle energies |
| title | Λ single particle energies |
| title_full | Λ single particle energies |
| title_fullStr | Λ single particle energies |
| title_full_unstemmed | Λ single particle energies |
| title_short | Λ single particle energies |
| title_sort | λ single particle energies |
| url | http://psasir.upm.edu.my/id/eprint/40238/ http://psasir.upm.edu.my/id/eprint/40238/ http://psasir.upm.edu.my/id/eprint/40238/ http://psasir.upm.edu.my/id/eprint/40238/1/%CE%9B%20single%20particle%20energies.pdf |