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.     

Decay of the 67-μs Isomer in ^142Pm

Excited states in ^142pm are investigated via the ^12sTe(^19F, 5n)^142pm reaction at beam energies from 75 to 95 MeV by using techniques of in-beam γ-ray spectroscopy. Measurements of γ-ray excitation function, X-γ and γ-γ-t coincidences are performed with 10 BGO(AC)HPGe detectors. Decay of the previously known 67-μs isomer in     

Triaxial interaction effect in the structure of ^148-158Sm

The structures of ^148-158Sm are studied in the frame of the interacting boson model. Attention is given to the triaxial interaction, and it is found that the triaxial interaction plays an important role in the detailed structure of this isotopic chain. The potential surfaces of these nuclei are also studied and the shapes of them are analysed. And it is found that though the triaxial interaction plays an important role in these nuclei, there are no stable triaxial shapes in the low-lying structures of these nuclei.     

Theoretical Analysis of the Exotic Structure of ^17F

The first excited state and the ground state of ^17F are studied with the asymptotic normalization coefficient method. The results show that the probabilities of the last proton being out of the binding-potential in both the states are P = 59.71% and P = 27.61%, respectively. This means that the last nucleon in both the states of ^17F is far-extended beyond the range of nuclear force, especially in the first excited state. This result is also verified by the calculation of the density distributions of the last proton in ^17F. It is quantitatively confirmed that the first excited state of^1TF is a nuclear halo state and its ground state is a proton skin state.     

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.     

On the mass of the ss^- member of the 1^3D1 meson nonet

In the framework of Regge phenomenology and meson meson mixing, this paper estimates the mass of isoscalar state （ss^-） of the 1^3D1 meson nonet, and the results given by two different approaches are 1735.51 ± 59MeV and 1730.29 ±46.SMeV.     

A study on the decay of ^72As

The excited states of the ⁷²Ge nucleus were investigated in radioactive decay of ⁷²As. Three new transitions with 1996.58, 2125.59 and 2255.49keV have been found for the first time. One γ-ray with 912.09keV has been placed in the decay scheme for the first time, and the placement of 1938.88, 2116.79, 2785.59, 2833.03, 2950.69 and 3338.00keV γ-rays are confirmed again in the present work. One new level at 2027.72keV excitation energy is proposed. The level scheme was established and for a number of levels spin-parity assignments are suggested on the basis of logft values and γ-branching ratios.     

The mass of the isodoublet of the 2^1S0 meson nonet revisited

In the qq quark model, the states π（1300）, η（1295） and η（1475） are assigned as the 2^1S0 meson nonet. The mass of the isodoublet remains interesting and needs further confirmation in experiments. This paper employs the phenomenological trajectory on the （N, M^2）-plot and meson meson mixing methods to calculate the mass of this state, the calculated results are 1341 MeV and 1311.58 ± 59 MeV respectively. These predictions can be compared with experiments in the future.[第一段]     

Development of the Neck in Fusion Reactions ^40Ca＋^90,96Zr

The neck dynamics and nucleon transfer through the neck in fusion reactions ^40Ca ^90,96Zr are studied by applyingthe improved quantum molecular dynamics model. A special attention is paid to the dynamic behaviour of the neck development at touching point and to the contribution of excess neutrons in a neutron-rich target (or projectile) to neck formation and nucleon transfer.     

High-Resolution Spectra of the ^10B^18O and ^11B^18O： Rotational Analysis of the B-X Bands

Emission spectra of ^10B^18 O and ^11B^18 O isotopomers in the 230-330nm region have been investigated by means of conventional high-resolution spectroscopy. The molecules were produced in a low-pressure arc by discharging 8 Torr of mixture containing argon and oxygen 18 in the ratio of 4:1 and the spectra have been recorded using Ebert-type spectrograph. The boron needed to produce BO has been present in the system as amorphous powder with natural abundance of ^10B and ^11B. Rotational analysis of the 0, 0 and 0, 1 bands has been performed and spectroscopic constants have been extracted. The results have allowed first determination of the equilibrium rotational constants Be and De for both isotope species ^10B^18O and ^11B^18O in their lower electronic state.Assuming a linear dependence of Be on (v 1/2), the value of equilibrium distance re in the lower state has been derived.     

Structures of ^17F and ^17O, ^17Ne and ^17N in the Ground State and the First Excited State

The structures of two couples of mirror nuclei ^17F and ^17O, ^17Ne and ^17N in the ground state and in the first excited state are investigated using the relativistic mean-field approach. Two-proton halo in ^17Ne in the first excited state and in the ground state and two-neutron halo in ^17N in the first excited state are suggested.Meanwhile, one-proton halo in ^17F in the first excited state and one-neutron halo in ^17O in the first excited state are also suggested. The skin structure appears in ^17F and ^17N in the ground state.     

Role of the Λ(1600) in the K^-p→Λπ^0π^0 reaction

Role of theΛ(1600)is studied in the K^-p→Λπ^0π^0 reaction by using the effective Lagrangian approach near the threshold.We perform a calculation for the total and differential cross sections by considering the contributions from theΛ(1600)andΛ(1670)intermediate resonances decaying intoπ^0∑^*0(1385)with∑^*0(1385)decaying intoπ^0Λ.Additionally,the non-resonance process from u-channel nucleon pole is also taken into account.With our model parameters,the current experimental data on the total cross sections of the K^-p→Λπ^0π^0 reaction can be well reproduced.It is shown that we really need the contribution from the A(1600)with spin-parity J^P=1/2^+,and that these measurements can be used to determine some of the properties of theΛ(1600)resonance.Furthermore,we also plot theπ0Λinvariant mass distributions which could be tested by the future experimental measurements.     

Radius of ^9C from the Asymptotic Normalization Coefficient

The asymptotic normalization coefficient (ANC) of^9C=^8B p deduced from S Li(d, p)^9 Li reaction is used to obtain the root-mean-square (rms) radius of the loosely bound proton in the ^9C ground state. We obtain (r^2)1/2 = 3.61 fm for the valence proton, which is significantly larger than the matter radius of ^9C. The probability of the valence proton outside the matter radius of ^9C is greater than 60%. The present work supports the conclusion that ^9C has a proton halo structure.     

Exact Solutions of the φ^6 ＋ φ^5 Model Using Truncated Method

In this letter, the φ^6 ＋ φ^5 model in （D ＋ 1） dimensions can be solved by a truncated series method. A series of solitary solutions of the φ^6 ＋ φ^5 model in （D ＋ 1） dimensions have be obtained.     

The theoretical character of the X^1∑^＋ and A^1∑^＋ states of ScN

This paper calculates the potential energy curves (PECs) of the ground state (X 1 Σ + ) and excited state (A 1 Σ + ) of ScN molecule by multireference configuration interaction method. The correct character of the PECs has been gripped while they had been improperly reported in the literature. Based on the PECs, the spectroscopic parameters and vibrational energy levels are determined, and compared with experimental data and other theoretical works available at the present.     

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.     

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.     

Theoretical Calculation of Rotational Bands of ^179Pt in the Particle-Triaxial-Rotor Model

Theoretical calculations have been performed for nucleus ^179Pt in the particle-triaxial-rotor model with variable moment of inertia. The obtained energy spectrum agrees with the experimental data quite well. The calculated results indicate that the bands 1/2^- and 7/2^ are triaxial deformation bands and originate mainly from the v[521]1/2^- and v[633]7/2^ configurations respectively.