Properties of the Alpha Decay Chain Nuclei of ^310 126, ^292 120 and ^298 114

The properties of the a decay nuclei of^310 126, ^292 120 and ^298 114 are investigated in the deformed relativistic meanfield model. The nuclear properties are investigated with the TMA and NL-Z2 parameter sets, and compared with Moller‘s result [At. Data Nucl. Data Tables 59 (1995) 185]. The results show that the a decay energy increases systematically with the increasing proton number. Meanwhile, the a decay energy has a minimum value at the point of shell closure. It is also found that among the three nuclei, ^292 120 is more possible to be the next doubly magic nucleus.     

Effects of Target Deformation on the Synthesis of Superheavy Nucleus 283^112

We investigate the effects of target deformation on the synthesis of superheavy nucleus 283^112 in the framework of the extra-push model. Our results show that the cross sections of the 3n evaporation residue in the 48^Ca 238^U reaction for the case of β2=0.275 are several times larger than those of β2=0. Meanwhile, the peak position of ER excitation function in the case of the deformed target is shifted to lower energy as compared to that of the spherical target.     

Identical Bands and Alignment in ^193,194Tl

The microscopic mechanism of the identical bands in odd-odd nucleus ^194Tl and its neighbour odd-A nucleus ^193Tl are investigated using the particle-number conserving method with monopole and quadrupole pairing interaction. It is found that the blocking effect plays an important role in the variation of moments of inertia (J^(1) and J^(2)) with rotational frequency for the superdeformed bands and identical bands. The alignment of 194T1 bands with respect to the ^193Tl(1) band used as a reference is also discussed.     

Measurement of ^2H（^8Li, ^9Be）n Reaction Relevant to Primordial Nucleosynthesis

The angular distribution of the ^2H（^8Li, ^9Be）n （ground state） reaction, important to primordial nucleosynthesis in the inhomogeneous model, has been measured at E = 8.1 MeV using a secondary ^8Li beam. Cross section of this reaction was determined to be 9.0 4±3.4 mb. According to the cross section, the astrophysical S-factor was calculated to be 272 4±103 keV b. It is shown that ^2H（8^Li, ^9Be）n （ground state） reaction is important for creating 9Be, but less important for destroying aLl in primordial nucleosynthesis.     

Effect of Conversion Process （≡^－P→AA） in ≡－－Hypernuclei

Effect of conversion process (≡^-P→AA) on ≡--hypernucleus is studied for ≡^12-Be. It is found that the conversion process has a certain extent effect on properties of low-lying states of the ≡^--hypernuclei.     

Synthesis of ^197Os

An isotope at a particular region in the chart of nuclides can be produced with a certain type ot nuclear reactions and experimental approaches. The (n, 2p) reaction is one of useful techniques for producing heavy neutron-rich nuclei in region not accessible from fission. In the present experiment, ^197Os was produced by using ^198Pt(n, 2p)^197Os reaction.     

Neutrino Energy Loss by Electron Capture on Nucleus ^56Mn, ^56Fe, ^56Co and ^56Ni in Strong Electron Screening

Based on the p-f shell model, the neutrino energy loss rates for nucleus ^56Mn, ^56Fe, ^56Co and ^56Ni in the electron capture process are canvassed in and not in a strong electron screening. The results show that the neutrino energy loss rates for ^56Mn, ^56Fe, ^56Co and ^56Ni decrease about 15%, 10%, 60% and i order of magnitude correspondingly at the temperature T9 = 15 and even debase 2 orders of magnitude at the temperature T9 = 1.     

Theoretical Investigation of the Exotic Structure of the Mirror Nuclei ^17Ne and ^17N

The exotic structures of the ground state of the mirror nuclei ^17Ne and ^17N are investigated by means of the asymptotic normalization coefficient （ANC） method to explore the role of the Coulomb interaction, The probebilities of a valence nucleon outside the binding-potential are P = 56.69±2.98/7.46% for ^17Ne and P = 45.51±2.32/5.81% for ^17N. The rms radii are （r^2）^1/2 = 5.06±0.11/0.30 fm and （r^2）^1/2=4.24±0.06/0.16 fm, respectively. The results obtained are nearly independent of the potential parameters. According to the halo occurrence conditions, it is suggested that ^17Ne is a two-proton halo and ^17N is a two-neutron skin. Moreover, two effects of the Coulomb interact-ion on the exotic structure are analysed. From the present results, the exotic structure of the nucleus in the proton-rich side is more obvious than that of its mirror nucleus because of the Coulomb interaction.     

Is Kano-Nucleon Interaction Consistent with Pentaquark θ^＋

The quark-delocalization colour-screening model is employed to calculate the effective potential between nucleon and kaon. The results show that the potentials are attractive in the I = 0 channel and repulsive in the I = 1 channel. The interactions are very weak between K^＋n or K^0p due to the cancellation between I = 0 and I = 1. It is possible to have a high s-wave resonance （1615 MeV）, but the width may be too wide to be observed in the experiments.     

10^—9K温度下的核磁有序

电子可以发生自发磁有序,导致铁磁等现象的产生.同样地,原子核也可以自发地有序排列.由于核磁矩比电子磁矩小得多,自发的核磁有序只能在极低温下发生.在研究核有序的过程中,我们所得到的自旋温度在铜中低达25nK,在银中达到了2nK. 电子的磁性所产生的有序现象,温区从几个mK到高于室温.而在核中,只有当原子核的磁偶极矩的热运动能kT比它们的相互作用能小的时候,才会发生自发的磁有序.由于核磁矩比电子磁矩小三个数量级,而偶极相互作用正比于磁矩的平方,所以核自旋系统的有序要低于μK的温度.固体3He是个例外,它的强的零点运动造成的电子波…     

Measurement of the Breakup Cross Sections in ^6He＋^9Be Reaction at 25 MeV／Nucleon

The breakup reaction cross sections were measured for the reaction of^6He at 25 MeV/nucleon from ^9Be target with intensity of 10^5 pps. By fitting the energy spectra of breakup α particles with Gaussian functions, the angular distribution of differential cross sections in the laboratory system has been extracted and compared with the Serber model calculations. The good agreement between the calculation and the experimental data favours a dominant configuration of the ^4He core plus valence neutrons for the structure of^6He.     

Calculation of Energy Levels of Nucleus ^127I in the Particle-Triaxial-Rotor Model

Theoretical calculations have been performed for nucleus ^127I in the framework of the particle-triaxial-rotor model.The calculated results indicate that both the 5^ /2 and 7^ /2 bands are oblate deformed bands.Their comfigurations are associated with the πd5/2[402]5/2 and πg7/2[404]7/2 orbitals and the strong mixing between them.Meanwhile a possible explanation of the strong mixing is given.     

One-Proton Halo Structure in ^23Al

The Glauber theory is used to investigate the reaction cross section of proton-rich nucleus ^23Al. A core plus a proton structure is assumed for ^23Al. HO-type density distribution is used for the core while the density distribution for the valence proton is calculated by solving the eigenvalue problem of Woods-Saxon potential The transparency function in an analytical expression is obtained by adopting multi-Gaussian expansion for the density distribution. Coulomb correction and finite-range interaction are introduced. This modified G1auber model is suitable for halo nuclei. A dominate s-wave is suggested for the last proton in ^23Al from our analysis which is possible in the calculation of relativistic mean-field theory.     

新滴线核^40Mg和^42，43 Al

众所周知,原子核是由质子和中子通过核子间的强相互作用结合而成的,元素的定义由核内的质子数确定,同一种元素可以有数目不等的同位素,区别就在于核内中子数目的多寡．以中子数和质子数为坐标,对核素排列做图,此图称为核素图．