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تسجيل مستخدم جديدCharacterization of the proposed 4-{alpha} cluster state candidate in 16O
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The $mathrm{^{16}O}(alpha, alpha^{prime})$ reaction was studied at $theta_{lab} = 0^circ$ at an incident energy of $textrm{E}_{lab}$ = 200 MeV using the K600 magnetic spectrometer at iThemba LABS. Proton and $alpha$-decay from the natural parity states were observed in a large-acceptance silicon-strip detector array at backward angles. The coincident charged particle measurements were used to characterize the decay channels of the $0_{6}^{+}$ state in $mathrm{^{16}O}$ located at $E_{x} = 15.097(5)$ MeV. This state is identified by several theoretical cluster calculations to be a good candidate for the 4-$alpha$ cluster state. The results of this work suggest the presence of a previously unidentified resonance at $E_{x}approx15$ MeV that does not exhibit a $0^{+}$ character. This unresolved resonance may have contaminated previous observations of the $0_{6}^{+}$ state.
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Inelastic $alpha$ scattering on 16O is studied at 400 MeV by using an ice target. Near the 4-alpha breakup threshold of 14.4 MeV, a broad peak is observed at an excitation energy of 13.6+/-0.2 MeV with a width of 0.6+/-0.2 MeV. The spin-parity is est
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