# Exploring the unknown Lambda-neutron interaction

## Abstract

No published \Lambda $\Lambda $ n scattering data exist. A relativistic heavy-ion experiment has suggested that a \Lambda $\Lambda $ nn bound state was seen. However, several theoretical analyses have cast serious doubt on the bound-state assertion. Nevertheless, there could exist a three-body \Lambda $\Lambda $ nn resonance. Such a resonance could be used to constrain the \Lambda $\Lambda $ n interaction. We discuss \Lambda $\Lambda $ nn calculations using nn and \Lambda $\Lambda $ n pairwise interactions of rank-one, separable form that fit effective range parameters of the nn system and those hypothesized for the as yet unobserved \Lambda $\Lambda $ n system based upon four different \Lambda $\Lambda $ N potentials. The use of rank-one separable potentials allows one to analytically continue the \Lambda $\Lambda $ nn Faddeev equations onto the second complex energy plane in search of resonance poles, by examining the eigenvalue spectrum of the kernel of the Faddeev equations. Although each of the potential models predicts a \Lambda $\Lambda $ nn sub-threshold resonance pole, scaling of the \Lambda $\Lambda $ n interaction by as little as \sim $\sim $ 5% does produce a physical resonance. This suggests that one may use photo-(electro-)production of the \Lambda $\Lambda $ nn system from tritium as a tool to examine the strength of the \Lambda $\Lambda $ n interaction.

- Authors:

- American Physical Society
- Flinders University

- Publication Date:

- Sponsoring Org.:
- USDOE

- OSTI Identifier:
- 1601517

- Grant/Contract Number:
- AC52-06NA25396

- Resource Type:
- Published Article

- Journal Name:
- SciPost Physics Proceedings

- Additional Journal Information:
- Journal Name: SciPost Physics Proceedings Journal Issue: 3; Journal ID: ISSN 2666-4003

- Publisher:
- Stichting SciPost

- Country of Publication:
- Country unknown/Code not available

- Language:
- English

### Citation Formats

```
Gibson, Benjamin, and Afnan, Iraj. R. Exploring the unknown Lambda-neutron interaction. Country unknown/Code not available: N. p., 2020.
Web. doi:10.21468/SciPostPhysProc.3.025.
```

```
Gibson, Benjamin, & Afnan, Iraj. R. Exploring the unknown Lambda-neutron interaction. Country unknown/Code not available. doi:10.21468/SciPostPhysProc.3.025.
```

```
Gibson, Benjamin, and Afnan, Iraj. R. Tue .
"Exploring the unknown Lambda-neutron interaction". Country unknown/Code not available. doi:10.21468/SciPostPhysProc.3.025.
```

```
@article{osti_1601517,
```

title = {Exploring the unknown Lambda-neutron interaction},

author = {Gibson, Benjamin and Afnan, Iraj. R.},

abstractNote = {No published \Lambda Λ n scattering data exist. A relativistic heavy-ion experiment has suggested that a \Lambda Λ nn bound state was seen. However, several theoretical analyses have cast serious doubt on the bound-state assertion. Nevertheless, there could exist a three-body \Lambda Λ nn resonance. Such a resonance could be used to constrain the \Lambda Λ n interaction. We discuss \Lambda Λ nn calculations using nn and \Lambda Λ n pairwise interactions of rank-one, separable form that fit effective range parameters of the nn system and those hypothesized for the as yet unobserved \Lambda Λ n system based upon four different \Lambda Λ N potentials. The use of rank-one separable potentials allows one to analytically continue the \Lambda Λ nn Faddeev equations onto the second complex energy plane in search of resonance poles, by examining the eigenvalue spectrum of the kernel of the Faddeev equations. Although each of the potential models predicts a \Lambda Λ nn sub-threshold resonance pole, scaling of the \Lambda Λ n interaction by as little as \sim ∼ 5% does produce a physical resonance. This suggests that one may use photo-(electro-)production of the \Lambda Λ nn system from tritium as a tool to examine the strength of the \Lambda Λ n interaction.},

doi = {10.21468/SciPostPhysProc.3.025},

journal = {SciPost Physics Proceedings},

number = 3,

volume = ,

place = {Country unknown/Code not available},

year = {2020},

month = {2}

}

DOI: 10.21468/SciPostPhysProc.3.025

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