New measurement of 4^(H)e and proton decays from resonant states in^(19)Ne

A^(6)Li(^(16)O,^(19)Ne^(∗))^(3)H multi-nucleon transfer-reaction experiment was performed to populate the highly excited states in^(19)Ne.The subsequent decay particles,^(4)He or protons from the^(19)Ne resonant states,were detected in coincidence with the recoil 3 H.The excitation-energy spectra of^(19)Ne were reconstructed using the detected proton or^(4)He and the deduced^(18)F or^(15)O data,respectively.A broad resonance at about 7.85 MeV(1/2^(+))was observed,with partial decay widths different from the previously reported values,which may have a significant impact on the destruction of 18 F in astrophysical processes.Several resonances up to very high excitation energies have been identified with a largeα-clustering strength,which confirm the formation of the cluster structure with a one-hole configuration in light nuclei and encourage further systematic studies of the cluster structure in^(19)Ne.

α-cluster decay from ^(24)Mg resonances produced in the ^(12)C(^(16)O,^(24)Mg)α reaction

A transfer reaction and cluster-decay experiment,12C(16O,24Mg→ α+20Ne)α, was performed at a beam energy of 96 MeV. Both recoil and decay α particles were detected in coincidence, allowing us to deduce the energymomentum of a20Ne fragment. A number of resonant states of24Mg were reconstructed up to an excitation energy of approximately 30 MeV. Owing to the experimentally achieved excellent resolutions of the Q-value and excitationenergy spectra, the relative decay widths for each resonant state in24Mg to various final states of20Ne were extracted, along with the total decay width. The obtained results provide good testing ground for theoretical descriptions of multiple clustering configurations in24Mg.

Bayesian analysis on non-resonant behavior of 12C+12C fusion reaction at sub-barrier energies

Controversies exist among experiments and theories on the S^(*)factor of the astrophysical important reaction ^(12)C+^(12)C for energies below 3 MeV.Only frequentist approaches have been used so far for data analysis,and the confidence levels or theoretical errors are not available from previous theoretical predictions.In this study,the Bayesian method is employed to provide theoretical predictions and its 1σconfidence level based on all the currently available experimental data for the first time.The improved coupled-channels model CCFULL-FEM implemented with the finite element method as well as the Markov chain Monte Carlo approach emcee are adopted to analyze the non-resonant behavior of this reaction.The posterior distribution of the Woods-Saxon potential parameters is investigated.Compared with the widely used frequentist method MIGRAD within the Minuit minimization program,the Bayesian method has a significant advantage for exploring the potential parameter space.When the existing experimental data measured down to subbarrier energies are considered,the potential parameters are constrained to a very narrow range,and the predictions of the S^(*) factor showed no sharp decrease in the low-energy region.