The $\eta {-}^3$He scattering length revisited

Abstract

The possible existence of $\eta$-mesic nuclei poses an interesting and still open issue of research. Since the occurence of such $\eta$-nucleus bound states is reflected in the corresponding $\eta$-nucleus scattering length, we critically review the present knowledge for the $\eta$${}^3$He system. Specifically, we scrutinize the available experimental information for the reaction $p+d\to \eta {+}^3\mathrm{He}$ which is commonly used to extract the $\eta$${}^3$He scattering length. We point out several striking discrepancies between the various measurements. Subject to those inconsistencies we deduce a value of $a=|4.3\pm 0.3|+i(0.5\pm 0.5)$ fm.

8 pages, 9 figures, accepted for publication in Eur. Phys. J. A

References in corpus (10)

• Near-Threshold Production of $\eta$-Mesons
• Formation of $\eta$-mesic Nuclei Using the Recoilless (d,${}^3$He) Reaction
• Are there eta-Helium bound states?
• Dependence of calculated binding energies and widths of $\eta$-mesic nuclei on treatment of subthreshold $\eta$-nucleon interaction
• Eta-N Final State Interaction in incoherent Photoproduction of Eta-mesons from the Deuteron near Threshold
• Measurement of p + d -> 3He + eta in S(11) Resonance
• The $\eta$-3N problem with separable interactions
• Threshold scattering of the eta-meson off light nuclei
• On eta-pi mixing close to the eta-Helium threshold
• Charge symmetry breaking as a probe for the real part of eta--nucleus scattering lengths

Cited by in corpus (13)

• Measurement of the dp -->3He eta reaction near threshold
• Is there an eta-3He quasi--bound state ?
• eta-Nucleon Scattering Length and Effective Range uncertainties
• Interaction of eta mesons with nuclei
• Determination of the ${\mathbf{\eta }}^3\mathrm{He}$ threshold structure from the low energy $\mathbf{pd}\to {\mathbf{\eta }}^3\mathrm{He}$ reaction
• Search for Quasi Bound $\eta$ Mesons
• Eta-mesic nuclei: past, present, future
• Possible eta-mesic 3He states within the finite rank approximation
• Study of the 3He-eta system in d-p collisions
• Eta-nuclear interaction: optical vs. coupled channels
• Systematic few-body analysis of eta-d, eta-3He and eta-4He interaction at low energies
• Binding vs. scattering length: $\eta$ in light nuclei
• Non-Strange Meson Production with Hadronic Probes