First measurement of the 2.4 and 2.9 MeV ${}^6$He three-cluster resonant states via the ${}^3$H(${}^4$He,p$\alpha$)2n four-body reaction

Abstract

Two new low-lying ${}^6$He levels at excitation energies of about 2.4 and 2.9 MeV were observed in the experimental investigation of the p-$\alpha$ coincidence spectra obtained by the ${}^3$H(${}^4$He,p$\alpha$)2n four-body reaction at $E_{{}^4\mathrm{He}}$ beam energy of 27.2 MeV. The relevant $E^{\ast }$ peak energy and $\Gamma$ energy width spectroscopic parameters for such ${}^6$He${}^{\ast }$ excited states decaying into the $\alpha$+n+n channel were obtained by analyzing the bidimensional ($E_{\mathrm{p}}$, $E_{\alpha }$) energy spectra. The present new result of two low-lying ${}^6$He${}^{\ast }$ excited states above the ${}^4$He+2n threshold energy of 0.974 MeV is important for the investigation of the nuclear structure of neutron rich light nuclei and also as a basic test for theoretical models in the study of the three-cluster resonance feature of ${}^6$He.

arXiv comment16 pages, 7 figures, 2 tables, accepted for publication in Mod. Phys. Lett. A

References in corpus (10)

• Ab initio shell model with a genuine three-nucleon force for the p-shell nuclei
• Quantum Monte Carlo calculations of excited states in A = 6--8 nuclei
• Discrete and continuum spectra in the unified shell model approach
• Resonances of 7He in the complex scaling method
• Effective Interaction Techniques for the Gamow Shell Model
• Three-body resonances by complex scaling
• Excitations in the Halo Nucleus He-6 Following The Li-7(gamma,p)He-6 Reaction
• The high-lying ${}^6$Li levels at excitation energy around 21 MeV
• Search for excited states in H-3 and He-3
• Experimental evidence of the ${}^6$He level at $E^{\ast }$ = 18.3 MeV by the ${}^4$He+${}^3$H three-body reaction

Cited by in corpus (1)

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