Positive-parity linear-chain molecular band in ${}^{16}$C

Abstract

An inelastic excitation and cluster-decay experiment ${}^2\mathrm{H}{(}^{16}\mathrm{C},{}^4\mathrm{He}+{}^{12}\mathrm{Be}\mathrm{or}{}^6\mathrm{He}+{}^{10}\mathrm{Be}){}^2\mathrm{H}$ was carried out to investigate the linear-chain clustering structure in neutron-rich ${}^{16}\mathrm{C}$. For the first time, decay-paths from the ${}^{16}\mathrm{C}$ resonances to various states of the final nuclei were determined, thanks to the well-resolved $Q$-value spectra obtained from the three-fold coincident measurement. The close-threshold resonance at 16.5 MeV is assigned as the $J^{\pi }=0^{+}$ band head of the predicted positive-parity linear-chain molecular band with $(3/2_{\pi }^{-}{)}^2(1/2_{\sigma }^{-}{)}^2$ configuration, according to the associated angular correlation and decay analysis. Other members of this band were found at 17.3, 19.4, and 21.6 MeV based on their selective decay properties, being consistent with the theoretical predictions. Another intriguing high-lying state was observed at 27.2 MeV which decays almost exclusively to ${}^6\mathrm{He}+{}^{10}\mathrm{Be}(\sim 6\mathrm{MeV})$ final channel, corresponding well to another predicted linear-chain structure with the pure $\sigma$-bond configuration.

6 pages, 4 figures

References in corpus (5)

• High precision probe of the fully sequential decay width of the Hoyle state in ${}^{12}$C
• Experimental investigation of a linear-chain structure in the nucleus 14C
• Selective decay from a candidate of the $\sigma$-bond linear-chain state in ${}^{14}$C
• 3alpha clustering in the excited states of 16C
• Evidence for Triangular D'(3h) Symmetry in 13C

Cited by in corpus (5)

• Observation of the near-threshold intruder $0^{-}$ resonance in ${}^{12}$Be
• Construction and commissioning of the collinear laser spectroscopy system at BRIF
• The study of the alpha formation probability in 10Be and 12Be within the microscopic cluster model
• $\alpha$-cluster decay from ${}^{24}$Mg resonances produced in ${}^{12}$C(${}^{16}$O,${}^{24}$Mg)$\alpha$ reaction
• Property investigation for different wedge-shaped CsI(Tl)s