Probing the existence of η^3He mesic nucleus with a few-body approach

Abstract

Motivated by the two recent observations in the WASA-at-COSY detector, we investigate the ${\eta }^3$He nucleus with the $\eta NNN$ few body method. We construct the effective $s$-wave energy dependent $\eta N$ potential which reproduce the $\eta N$ subthreshold scattering amplitude in the 2005 Green-Wycech model. It gives the $\eta$ separation energy and decay width of 0.19 MeV and 1.71 MeV, respectively. We also construct various sets of effective $s$-wave energy independent $\eta N$ potentials where the corresponding complex scattering lengths (a) are within the range given in most theoretical models. We obtain the bound ${\eta }^3$He nucleus with decay width of about 5 MeV when a is (1.0 fm, 0.3 fm), and of about 10 MeV when a is (1.0 fm, 0.5 fm).

7 pages, 11 figures

References in corpus (7)

• Measurement of the dp -->3He eta reaction near threshold
• Meson-nucleus potentials and the search for meson-nucleus bound states
• Search for eta-mesic 4He in the dd->3He n pi0 and dd->3He p pi- reactions with the WASA-at-COSY facility
• Determination of the ${\mathbf{\eta }}^3\mathrm{He}$ threshold structure from the low energy $\mathbf{pd}\to {\mathbf{\eta }}^3\mathrm{He}$ reaction
• Onset of $\eta$-meson binding in the He isotopes
• Few-body calculations of $\eta$-nuclear quasibound states
• Search for the $\eta$ mesic ${}^3$He in the $pd\to dp{\pi }^0$ reaction with the WASA-at-COSY facility