Liu Zu-Hua

Excitation Halo States of 12B

Angular distributions for the 11B(d,p)12B transfer reactions have been measured at Elab = 11.8 MeV. The asymptotic normalization coefficients (ANC) of the ground state, the second and third excitation states for 12B (11B+n) are extracted from the differential cross sections at three forward angles. With these ANCs, the root-mean-square radii are calculated for these three states. The results show that the second and third excitation states of 12B are neutron halo states.

Experimental Evidence of Two-Proton Emissions from 18Ne Excited State

Experiment 18Ne+ 197Au was performed in Heavy Ion Research Facility Radioactive Ion Beam Line at Lanzhou (RIBLL). The nuclear energy levels of 18Ne were built by complete kinematical reconstruction of the decay products and diproton decay were observed from 18Ne excited states. At 6.15 MeV, the experimental relative momentum and angular correlations of the emitted protons are given. The obvious enhancement at |qrel| = 23 MeV/c and θc.m. = 40° shows the experimental criterion of 2He cluster decay from 18Neq.

Halo Nature of 14,15C

We have used spectroscopic factors extracted from the (d,p) transfer reactions to calculate asymptotic normalization coefficients and root-mean-square (rms) radii for the valence neutron in 14,15C. The obtained rms radii are 4.57±0.30, 5.78±0.36 and 5.82±0.60 fm for the first 1-, 0- excited states of 14C and the ground state of 15C, which are 1.84, 2.33 and 2.32 times larger than the size of their cores, respectively. These large values imply that 15C as well as 14C in its first 1-, 0- states are halo nuclei.

Nuclear halo effect on nucleon capture reaction rates at stellar energies

The capture cross sections at stellar energies are very difficult to measure directly. Hence, data are usually evaluated by using indirect methods or extrapolations from the experimental data obtained at the lowest possible energies. The asymptotic normalization coefficient (ANC) approach of the transfer reactions provides a reliable way for the determination of the capture cross sections at stellar energies. By virtue of its reliability, we have calculated the capture cross sections of the 10Be(n,γ)11Be reaction by using nuclear ANC method. 11Be is a well-known neutron halo nucleus with two weakly bound states. As a typical example, we have shown that the radiative cross sections for a nucleon captured into a halo state are obviously enhanced. The enormous enhancement of the capture cross section is just due to the large overlap of the incident neutron wave with the extended tail of the halo. The 10Be(n,γ)11Be capture reaction is involved in the inhomogeneous big-bang nucleosynthesis. We have evaluated its reaction rates at stellar energies with the nuclear ANC method.

Experimental Study of Beta-Delayed Proton Emission of 36,37Ca

The investigation of beta-delayed proton decay mode has become a powerful probe to study the proton-rich nuclei and their nuclear structure. To study exotic nuclei with extremely low purity produced by the Radioactive Ion Beam Line in Lanzhou, we perform an experiment of beta-delayed proton emission of 36,37Ca under a high-intensity continuous-beam mode. Ions are implanted into a double-sided silicon strip detector, where the subsequent decays are correlated to the preceding implantations in time sequence. The energy spectra of delayed protons from 36,37Caβ decay, half-lives and decay branching ratios are measured. The experimental results confirm the previous literature data and some improved results are obtained as well, demonstrating the feasibility of our detection approach and the reliability of our data analysis procedure. This allows for the development of more powerful detection arrays and further research on nuclei closer to proton-drip line on the basis of present work.

Development of large-area quadrant silicon detector for charged particles *

The quadrant silicon detector, a kind of passivated implanted planar silicon detector with quadrant structure on the junction side, gained its wide application in charged particle detection. In this paper, the manufacturing procedure, performance test and results of the quadrant silicon detector developed recently at the China Institute of Atomic Energy are presented. The detector is about 300

Effects of Target Deformation on the Synthesis of Superheavy Nucleus283112

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Possible Experimental Evidence of a Moderate Proton Halo in29S

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Extraction of the rms Radii of 13C from Asymptotic Normalization Coefficients

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The Role of Neck Evolution in the Synthesis of Superheavy Element 112

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