Institutional Repository of Institute of Modern Physics, CAS
Not a member yet
5769 research outputs found
Sort by
Consistent nucleon-nucleon potentials and three-body forces
No full textWe construct microscopic three-nucleon forces consistent with the Bonn and Nijmegen two-nucleon potentials, and including , Roper, and nucleon-antinucleon excitations. Recent results for the choice of the meson parameters are discussed. The forces are used in Brueckner calculations and the saturation properties of nuclear matter are determined
Orientation effects of deformed nuclei on the production of superheavy elements
No full textWithin the dinuclear system model, the effects of the relative orientations of interacting deformed nuclei on the interaction potential energy surfaces, the evaporation residue cross sections of some cold fusion reactions leading to superheavy elements are investigated. The competition between fusion and quasifission is studied to show the effect of the orientation. It turns out that the belly-belly orientation is in favor of the production of superheavy nuclei, because in the case a barrier has suppressed the quasifission and thus helped fusion.Natural Science Foundation of China 10505016
10775061
10475099
10435010
10705014
10575036
Chinese Academy of Sciences KJCX2-SW-N17
KJCX3-SYW-N02
DFG of Germany 2007CB81500
Application of laser-induced breakdown spectroscopy in analyzing microelements in three kinds of fruit samples
No full text激光诱导击穿光谱(LIBS)在植物样品上面的应用是一个较新的课题. 为将LIBS技术能实际应用于与食品安全相关的领域，实验中对三种真空冻干水果样品进行了初步LIBS实验研究，鉴别了其LIBS光谱，并选取典型光谱线，运用统计学方法分析比较了三种水果中Ca，Na，K，Fe，Al，Mg六种元素含量的差别. 实验结果表明，苹果中Na的含量最高，Ca的含量最低，三种水果样品中的K，Fe，Mg等元素含量也都有差异. 实验结果还表明LIBS技术是一种检测、对比植物样品中微量元素含量的有效手段.National Natural Science Foundation of China 1060503
L-shell ionization accompanied by one-electron capture in Cq+, Oq+ (q=2,3)-Ne collisions
No full textThe L-shell ionization processes of a Ne gas target associated with single-electron capture by bombardment of Cq+ and Oq+ (q=2,3) are investigated using the projectile-recoil-ion coincidence method in the energy range from 80 to 400 keV/u (v(p)=1.8-4 a.u.). The cross-section ratios (R-k1) of k-fold ionization to single capture are compared with the results for He2+-Ne collisions by Dubois [Phys. Rev. A 36, 2585 (1987)]. All the velocity dependences are quite similar. The ratios increase as the projectile energy increases in the lower-energy region, reach the maxima for projectile energies around E-max=160q(1/2) keV/u, and then decrease at higher energies. These results qualitatively agree with our calculations in terms of the Bohr-Lindhard model within the independent-electron approximation.National Natural Science Foundation of China 10704030
1030401
Scaling and the thermal conductivity of the Frenkel-Kontorova model
No full textWe have studied the dependence of the thermal conductivity kappa on the strength of the interparticle potential lambda and the strength of the external potential beta in the Frenkel-Kontorova model. We found that the functional relation can be expressed in a scaling form, kappa(proportional to) lambda 3/2/beta(2 center dot). This result is first obtained by nonequilibrium molecular dynamics. It is then confirmed by two analytical methods, the self-consistent phonon theory and the self-consistent stochastic reservoirs method. The thermal conductivity kappa is therefore a decreasing functon of beta and an increasing function of lambda.Hong Kong Research Grants Council RGC
Hong Kong Baptist University Faculty Research Grant FRG
Chinese Academy of Sciences and China National Natural Science Foundation 1077515
Outline of the progress in the study of radioactive nuclear physics and super-heavy nuclei
No full textWe briefly introduce the current status and progress in the field of radioactive ion beam physics and the study of super-heavy nuclei. Some important problems and research directions are outlined, such as the sub-barrier fusion reaction, the direct reaction at Fermi energy and high energies, the property of nuclei at drip-lines, new magic numbers and new collective motion modes for unstable nuclei and the synthesis and study of the super-heavy nuclei.National Basic Research Program of China 2007CB815000
2005CB724800
National Natural Science Foundation of China 10775003
10475004
10405001
1022100
High precision mass measurement and LPT
No full textA Penning trap, which can measure the atomic masses with the highest precision, is one of the most important facilities in nuclear physics research nowadays. The precision mass data play an important role in the studies of nuclear models, mass formulas, nuclear synthesis processes in the nuclear astrophysics, symmetries of the weak interaction and the conserved vector current (CVC) hypothesis. The status of high precision mass measurement around the world, the basic principle of Penning trap and the basic information about the LPT (Lanzhou Penning Trap) are introduced.National Natural Science Foundation of China 10627504
10675147
10221003
Knowledge Innovation Project of Chinese Academy of Sciences KJCX2-SW-N17
KJCX2-SW-N18
Major State Basic Research Development Program of China 2007CB81500
Rotation-driven prolate-to-oblate shape phase transition in W-190: A projected shell model study
No full textA shape phase transition is demonstrated to occur in W-190 by applying the projected shell model, which goes beyond the usual mean-field approximation. Rotation alignment of neutrons in the high-j, i(13/2) orbital drives the yrast sequence of the system, changing suddenly from prolate to oblate shape at angular momentum 10h. We propose observables to test the picture
Influences of the isospin-dependence of in-medium nucleon nucleon cross-section and momentum dependent interaction on isoscaling parameter
No full textInfluences of the isospin-dependent in-medium nucleon nucleon cross-section (sigma(iso)(NN) and momentum-dependent interaction (MDI) on the isoscaling parameter a are investigated for two central collisions Ca-40 +Ca-40 and Ca-60+ Ca-60. These collisions are with isospin dependent quantum molecular dynamics in the beam energy region from 40 to 60 MeV/nucleon. The isotope yield ratio R-21 (N, Z) for the above two central collisions depends exponentially on the neutron number N and proton number Z of isotopes, with an isoscaling. In particular, the isospin-dependent (sigma(iso)(NN) and MDI induce an obvious de crease of the isoscaling parameter a. The mechanism of the decreases of a by both sigma(iso)(NN) and MDI are studied respectively
Structure of upper-g(9/2)-shell nuclei and shape effect in the Ag-94 isomeric states
No full textUsing a shell model which is capable of describing the spectra of upper g(9/2)-shell nuclei close to the N = Z line, we study the structure of two isomeric states 7(+) and 21(+) in the odd-odd N = Z nucleus Ag-94. It is found that both isomeric states exhibit a large collectivity. The 7(+) state is oblately deformed, and is suggested to be a shape isomer in nature. The 21(+) state becomes isomeric because of level inversion of the 19(+) and 21(+) states due to core excitations across the N = Z = 50 shell gap. Calculation of spectroscopic quadrupole moment indicates clearly an enhancement in these states due to the core excitations. However, the present shell model calculation that produces the 19(+)-21(+) level inversion cannot accept the large-deformation picture of Mukha et al