Search for the $\eta$ mesic ${}^3$He in the $pd\to dp{\pi }^0$ reaction with the WASA-at-COSY facility

Abstract

The excitation function for the $pd\to$ $dp{\pi }^0$ reaction has been measured by WASA-at-COSY experiment with the aim of searching for $^{3}\hspace{-0.03cm}\mbox{He}$-$\eta$ mesic nuclei. The measurement in the vicinity of $\eta$ meson production was performed using a ramped proton beam. The data analysis and interpretation was carried out with the assumption that the $\eta$-mesic Helium decays via the formation of an intermediate N${}^{\ast }$(1535) resonance. No direct signal of the $\eta$-mesic nucleus is observed in the excitation function. We determine a new improved upper limit for the total cross section for the bound state production and decay in the $pd\to$ $(^{3}\hspace{-0.03cm}\mbox{He}$-$\eta {)}_{bound}\to$ $dp{\pi }^0$ process. It varies between 13 nb to 24 nb for the bound state with width in the range $\Gamma \in (5,50)$ MeV.

References in corpus (12)

• Updated analysis of NN elastic scattering to 3 GeV
• Measurement of the dp -->3He eta reaction near threshold
• Meson-nucleus potentials and the search for meson-nucleus bound states
• The WASA Detector Facility at CELSIUS
• Determination of the eta'-proton scattering length in free space
• Measurement of excitation spectra in the ${}^{12}$C$(p,d)$ reaction near the ${\eta }^{\prime }$ emission threshold
• 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
• Production of $\eta$ and ${\eta }^{\prime }$ Mesons on Nucleons and Nuclei
• Onset of $\eta$-meson binding in the He isotopes
• Measurement of the $\eta \to {\pi }^{+}{\pi }^{-}{\pi }^0$ Dalitz plot distribution
• Study of the 3He-eta system in d-p collisions

Cited by in corpus (5)

• In-medium properties of the light and heavy-light mesons in a light-front quark model
• Resonance-like structure near the $\eta d$ threshold in the $\gamma d${$\to$}${\pi }^0\eta d$ reaction
• Status of the search for $\eta$-mesic nuclei with particular focus on $\eta$-Helium bound states
• Probing the existence of η^3He mesic nucleus with a few-body approach
• Feasibility of an experimental search for a resonance of a pion and a light nucleus