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2005 Vol. 22, No. 4

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Non-integer Quantum Transitions
ZHANG Qi-ren
2005, 22(4): 305-309. doi: 10.11804/NuclPhysRev.22.04.305
Abstract(2217) PDF (219KB)(586)
Abstract:
We prove that in the quantum transition of a system induced by the radiation of frequency v, the energy difference between the initial and the final states of the system is not necessarily being an integer multiple of hv. The Bohr condition for quantum transitions and the Einstein law for photo-electric effects are approximate results of perturbation. They are violated in the transitions induced by intense lasers.
Brain Science and Quantum Theory
QIU Xi-jun
2005, 22(4): 310-314. doi: 10.11804/NuclPhysRev.22.04.310
Abstract(2528) PDF (255KB)(841)
Abstract:
The present paper briefly reviews the relationship between biology and physics, especially including the classical physics models for the artificial neuron networks, some quantum theories for brains, and simply describes the structures and functions of cytoskeletal microtubules (MTs) in cells and some recent theoretical studies on MTs.Noting MTs are the important components and function units in cells and neurons, furthermore, the paper lays emphasis on our recent theoretical work on MTs. Particularly, based on the pseudo-spin quantum theory, the dynamic behavior of electrons on the MT wall has been discussed in some detail. Based on the quantum field theory, it has been described that the maser radiation might exist in the water molecular system within the MT.
Heavy Ion Fusion Reaction and Di-nuclear System Model
ZHAO En-guang, LI Jun-qing, W. Scheid
2005, 22(4): 315-322. doi: 10.11804/NuclPhysRev.22.04.315
Abstract(2490) PDF (333KB)(762)
Abstract:
In recent years, the Lanzou-Beijing-Giessen collaboration has studied the heavy ion reactions which are lead to the formation of super-heavy nuclei. The study emphases the mechanism of the fusion stage of the reactions. Based on the so called Di-nuclear System Model, some improvements have been made. The main points are the coupling of the dissipation of relative motion energy, angular momentum with nucleon transfer, and solving the Master equation in every step of the nucleon transfer with exact driving potentials, in order to describe the evolution of the system more microscopically. At the same time, we also discussed the effects of nuclear deformation and their relative orientation on the driving potentials, and studied the survive probability of the compound nuclei and its old-even effects, as well as the influence of inelastic excitations of nuclei in entrance channels to the capture cross sections.
Unified Description of Signature Inversion, Chiral and Wobbling Bands
CHEN Yong-shou, GAO Zao-chun
2005, 22(4): 323-328. doi: 10.11804/NuclPhysRev.22.04.323
Abstract(1962) PDF (201KB)(574)
Abstract:
The Reflection Asymmetric Shell Model has been generated to include the axial symmetry break. In this new development, the shell model space is spanned by the triaxially-deformed multi-quasi-particle basis. A unified shell model description of the signature inversion, chiral and wobbling bands can be achieved. In the frame work of shell model, the inclusion of the triaxiality, the exact three dimensional projection and up to six quasiparticle configuration mixing make the theory powerful to study the phenomena in highly rotating triaxial nuclei at a new level.
Investigation in Possibility of Producing Superheavy Fragments through Massive Nuclear Reactions at Low Energies
WU Xi-zhen, LI Zhu-xia, WANG Ning, TIAN Jun-long, ZHAO Kai, ZHANG Yin-xun, OU Li, LIU Min
2005, 22(4): 329-333. doi: 10.11804/NuclPhysRev.22.04.329
Abstract(2059) PDF (222KB)(576)
Abstract:
In this paper, the possibility of producing superheavy fragments through composite system breaking up in massive nuclear reactions is investigated. Two main theoretical models, which are the quantum fluctuations with in the fragmentation theory developed at 1980's and improved quantum molecular dynamics model developed recently by our group, are briefly reviewed. The dependence of the production probability of superheavy fragments on the incident energy, the decay mechanism of composite system and superheavy fragments, and the distribution of binding energy of Superheavy fragments are discussed for reactions of ^244Pu+^244Pu, ^238U+^238U, 197Au+^197Au based on the improved quantum molecular dynamics model.
Recent Advance in Plasma Turbulence Theory Research
QIU Xiao-ming, PENG Xiao-dong, LI Ji-quan, WANG Xiao-gang
2005, 22(4): 334-336. doi: 10.11804/NuclPhysRev.22.04.334
Abstract(2480) PDF (167KB)(638)
Abstract:
Progress of the research on the zonal flows in tokamak plasma turbulence is surveyed, especially it is reviewed that the zonal flows observed in the experiments and numerical simulations on atmosphere turbulence and ocean turbulence and the discovery of H-mode in tokamak experiments how lead the researchers in magnetic confinement fusion community to find out the existence of the zonal flow in tokamak plasma turbulence and subsequently give the experimental verification of its existence. Finally, the results of our research on zonal flow generation and evolution in resistive-g mode turbulence are presented in brief.
A Brief Introduction for Jefferson National Laboratory (JLab)
YE Yun-xiu, Lü Hai-jiang
2005, 22(4): 337-342. doi: 10.11804/NuclPhysRev.22.04.337
Abstract(3128) PDF (312KB)(672)
Abstract:
The general situation of JLab is briefly introduced. The accelerator CEBAF with high quality and the equipments in the three Halls are described. The experimental results with high accuracies, which were obtained by using continue beam with high energy resolution, and high density target and high resolution spectrometers in the halls, are presented with two examples. The basic physics problems which JLab intends to solve, and the programs which JLab completed and is going to do, are stated. The programs which China group is cooperating with other groups are emphasized. The energy escalation for CEBAF will bring new opportunities for scientific researches.
NuTeV Anomaly and Strange Quark-antiquark Asymmetry
MA Bo-qiang
2005, 22(4): 343-343. doi: 10.11804/NuclPhysRev.22.04.343
Abstract(1923) PDF (74KB)(612)
Abstract:
This talk summarized the results of using strange quark-antistrage quark asymmetry of the nucleon to explain the NuTeV anomaly. It is shown that asymmetric strange quark-antistrage quark distributions may be a reasonable explanation for the NuTeV defect. On the other side, the NuTeV anomaly could be the evidence for the existence of asymmetric strange-antistrange quark distributions.
Density-dependent Cluster Model Study of α-decay and Cluster Radioactivity of Nuclei
REN Zhong-Zhou, XU Chang
2005, 22(4): 344-350. doi: 10.11804/NuclPhysRev.22.04.344
Abstract(2534) PDF (299KB)(647)
Abstract:
We have discussed a new cluster model of α-decay and cluster radioactivity: the density-dependent cluster model (DDCM), which is based on the microscopic nuclear potential and Coulomb potential. DDCM can give accurate theoretical half-lives for various decays of nuclei in a unified framework. Through a systematical calculation of half-lives of α-decay and cluster radioactivity, we find that the deviation between DDCM and experiment is usually less than a factor of 3. This good agreement shows that the density-dependent cluster model can further provide reliable predictions for future experiments.
Brief Review on Frontiers of Nuclear Physics and Some Suggestions to NSFC
ZOU Bing-song
2005, 22(4): 351-353. doi: 10.11804/NuclPhysRev.22.04.351
Abstract(2398) PDF (148KB)(756)
Abstract:
A brief review is given on the frontiers of nuclear physics research. Some personal opinions and suggestions to the NSFC on the fields to have priority for support are presented.
Density Matrix in Quantum Mechanics and the Distinction of Ensembles Having the Same Density Matrix
LONG Gui-lu
2005, 22(4): 354-357. doi: 10.11804/NuclPhysRev.22.04.354
Abstract(2663) PDF (185KB)(817)
Abstract:
Density matrix is one important tool in quantum mechanics, and it has very broad applications. However there are different definitions about the density matrix, and they describe quite different systems. There has been some misunderstanding about the density matrix in the community, and these misunderstandings hinder the right application of the density matrix. In this article, we discuss the different definitions of density matrix. We suggest to use the full density matrix, compressed density matrix and the reduced density matrix to describe the state of a complete quantum system, the state of an averaged particle in an ensemble and the state of part of a composite system. We stress that contrary to the wide accepted understanding that ensembles with the same compressed density matrix are physically indistinguishable, they are distinguishable through the so-called ensemble measurement. As an application, we suggest that the present conclusion that the present-day nuclear magnetic resonance quantum computation does not have quantum entanglement is groundless.
Nuclear Shape Phase Transitions
MU Liang-zh, LIU Yu-xin
2005, 22(4): 358-366. doi: 10.11804/NuclPhysRev.22.04.358
Abstract(2580) PDF (453KB)(898)
Abstract:
We review the status of the research of nuclear shape phase transitions in this paper. Meanwhile, by taking the coherent state theory and angular momentum projection method, we study the shape phase transitions of axially symmetric even-even nuclei with U(5) symmetry, SU(3) symmetry and those in the transitional region of the two symmetries in the framework of Interacting Boson Model-1 (IBM-1), which does not distinguish the proton bosons from neutron bosons.
Learn New Mechanisms from Life
JI Qing, LUO Ming-yan, TONG Xiao-lin, ZHANG Bo, ZHANG Hui
2005, 22(4): 367-369. doi: 10.11804/NuclPhysRev.22.04.367
Abstract(2312) PDF (174KB)(531)
Abstract:
On the basis of the important experimental results of molecular motors, it was polnted out that the moving process of molecular motors is a coupling biological process of chemical-electrical-mechanical processes. This clever mechanism of energy conversion on the molecular level with several processes coupled together had never been observed before. The understanding of this new mechanism is an important step towards the understanding of life and an important content of what we can learn from life. We introduced here the status of the investigations on the mechanism for the force generation of kinesin and the studies of the authors in this field
Anomalous Diffusion: Directional Passing over the Saddle Point of a Potential
BAO Jing-dong
2005, 22(4): 370-372. doi: 10.11804/NuclPhysRev.22.04.370
Abstract(1863) PDF (160KB)(578)
Abstract:
Directional transport of a particle in a non-Ohmic environment passing over the saddle point of a potential is considered and the analytical expression of the passing probability is obtained. Our results has shown that both overshooting and backflow are observed in the case of subdiffusion. This is a possible for understanding slow increasing of the fusion probability with the center-of-mass energy.
Effect of Nuclear Fragmentation in Interactions of Heavy Ions with Biomolecules
ZHANG Feng-shou
2005, 22(4): 373-375. doi: 10.11804/NuclPhysRev.22.04.373
Abstract(1824) PDF (142KB)(576)
Abstract:
The effect of nuclear fragmentation discussed. The status and perspectives of this data. in the topic interactions of heavy ions with biological are presented based On calculations and molecules is experimental.
Hadron Properties in Chiral Sigma Model
SHEN Hong
2005, 22(4): 376-377. doi: 10.11804/NuclPhysRev.22.04.376
Abstract(2372) PDF (120KB)(492)
Abstract:
The modification of hadron masses in nuclear medium is studied by using the chiral sigma model, which is extended to generate the omega meson mass by the sigma condensation in the vacuum in the same way as the nucleon mass. The chiral sigma model provides proper equilibrium properties of nuclear matter. It is shown that the effective masses of both nucleons and omega mesons decrease in nuclear medium, while the effective mass of sigma mesons increases at finite density in the chiral sigma model. The resuits obtained in the chiral sigma model are compared with those obtained in the Walecka model, which includes sigma and omega mesons in a non-chiral fashion.
Systematic Study of Low-lying States in Atomic Nuclei
ZHAO Yu-min
2005, 22(4): 378-381. doi: 10.11804/NuclPhysRev.22.04.378
Abstract(1859) PDF (201KB)(555)
Abstract:
I would like to discuss low-lying systematics of NnNp suggested by Rick Casten, Nucleon-pair approximation of the nuclear shell model and its applications, and intrinsic properties of many-body systems in the presence of random interactions. I shall emphasize on backgrounds and perspectives of these problems, and summarize our basic understanding on these problems, after many efforts made by my collaborators and me.
Progress on Study of Quantum Secure Direct Communication
DENG Fu-guo, ZHOU Ping, LI Xi-han, LI Chun-yan, ZHOU Hong-yu
2005, 22(4): 382-386. doi: 10.11804/NuclPhysRev.22.04.382
Abstract(3036) PDF (255KB)(647)
Abstract:
The requirements of quantum secure direct communication (QSDC) are briefly introduced. Two QSDC schemes i. e. , the Two-Step QSDC scheme and the Quantum-One-Time-Pad QSDC scheme, are discussed in brief.
Cosmic Center-of-mass Frame
ZHANG Bang-gu
2005, 22(4): 387-390. doi: 10.11804/NuclPhysRev.22.04.387
Abstract(2471) PDF (191KB)(594)
Abstract:
According to astronomical observation we point out that the time of our expanding cosmic system can be discussed separating from the space. And the space in our universe is flat. In the cosmic center-of-mass frame(CCF), based on the temperature of CMBR, the cosmic density and the cosmic radii, the distance of the farmost galaxy, the total energy of our universe asa gravitation system has been calculated. It shows that our universe is in a gravitational bound state, and it will contract. In CCF the contracting progress is a synchronized freely falling body under initial condition of uniform distribution. Uder assumption of the symmetry of cosmic expanding and contracting progresses, th one-to-one correspondence of the expanding time to the temperature of CMBR can be obtained.
Spin Symmetry in Anti-nucleon Spectra in Atomic Nuclei
ZHOU Shan-gui, MENG Jie
2005, 22(4): 391-394. doi: 10.11804/NuclPhysRev.22.04.391
Abstract(1892) PDF (171KB)(623)
Abstract:
Two Foundational Problems in Monte Carlo Method
WANG Zhong-qi, SONG Yu-lin, XIAO Gang, ZHANG Ben-ai
2005, 22(4): 395-397. doi: 10.11804/NuclPhysRev.22.04.395
Abstract(1782) PDF (130KB)(1021)
Abstract:
The producation of random number and the sampling of random distribution are two foundational problems in Monte Carlo Mothed. In this paper, we carry out some new ways to treat the problems.
Radiation Induced DNA Damage and Related Bio-chemi-physical Problems
CAO Tian-guang, CAI Ming-hui, GENG Jin-peng, KONG Fu-quan, MA Yun-zhi, ZHUO Yi-zhong
2005, 22(4): 398-401. doi: 10.11804/NuclPhysRev.22.04.398
Abstract(1847) PDF (141KB)(519)
Abstract:
Some of recent works are presented on radiation induced DNA damage being carried out at China Institute of Atomic Energy (CIAE) and related bio-chemi-physical problems. Emphasis is placed on track structure and its relation to the cell end-point, and a simple model proposed to study the dynamical behavior of P53-Mdm2 interaction which plays pivotal role in cellular response to DNA damage.
Selected Topics in Intermediate and High Energy Nuclear Physics
LI Lei, ZHONG Xian-hui, NING Ping-zhi
2005, 22(4): 402-406. doi: 10.11804/NuclPhysRev.22.04.402
Abstract(2346) PDF (273KB)(600)
Abstract:
Several problems in intermediate and high energy nuclear physics have attracted considerable attention in these years: (1) Nucleon electromagnetic form factors. There is a systematic difference between the recently measured data from high energy polarized electron-nucleon scattering experiments and the previous Rosenbluth results. (2) The strength of K^- nucleus optical potentials. It varies qualitatively from different analyyses on K^- nucleus interactions. In this paper, the above problems are discussed and reviewed briefly.
Quantum Information Processing in the Wall of Microtubule
SHI Chun-hua, QIU Xi-jun
2005, 22(4): 407-410. doi: 10.11804/NuclPhysRev.22.04.407
Abstract(2277) PDF (156KB)(429)
Abstract:
Microtubule (MT) is described as an anisotropic two-dimensional pseudo-spin model on a triangular lattice, in which there are three different "spin-spin" interactions. The mobile electron in each lattice site is described based on the pseudo-spin model. Then, the processing of quantum information in the MT wall is presented by virtue of the scheme of driving quantum computer in sequence of laser pulse developed by Lloyd.
Quantum Coherence in Degenerate Cascade Three-level Atom Driven by Laser Field
LIU Wan-fang, ZENG Guo-mo
2005, 22(4): 411-415. doi: 10.11804/NuclPhysRev.22.04.411
Abstract(1802) PDF (188KB)(596)
Abstract:
Quantum coherence effects in degenerate cascade three-level atom subject to magnetic field are investigated. One-photon EIT, two-photon EIT and two-photon EIA are obtained, due to the coherence between the drive Rabi frequency and Zeeman splitting.
Researching on Brownian Dynamics of Potassium Ion Channel
AN Hai-long, ZHANG Su-hua, HAN Ying-rong, XIE Ning, ZHAO Tong-jun, ZHAN Yong
2005, 22(4): 416-418. doi: 10.11804/NuclPhysRev.22.04.416
Abstract(2150) PDF (143KB)(581)
Abstract:
In the paper, based on the first principle and the X-ray structure of the potassium ion channel, the potential curve is calculated by the density functional theory. And forced by the potential, the dynamical properties of K channels are also studied.
Injection Mechanism of Helium Atom into Wall-defective Carbon Nanotube
JIN Nian-qing, HU Yong-jin, ZHAO Jiang, ZENG Xiang-hua
2005, 22(4): 419-421. doi: 10.11804/NuclPhysRev.22.04.419
Abstract(2101) PDF (164KB)(579)
Abstract:
Based on the classical molecular processes of He atom into SWCNT with wall dynamics method and TLHT potential model, the injection defects of different radius are studied. The calculated results indicate that there are four typical moving patterns of He atom with different injective energy and the size of wall defects make a great difference to the absorption and storage behavior of He into SWNT.
Stability of Color-flavor-locked Phase and Its Phase Transition
FANG Chun-yu, ZHANG Xiao-bing, NING Ping-zhi
2005, 22(4): 422-428. doi: 10.11804/NuclPhysRev.22.04.422
Abstract(2701) PDF (341KB)(495)
Abstract:
Quark matter at high density has a rich phase structure. Goidstone-mode may condense in the color-flavor-locked (CFL) phase matter. We review the stability of CFL phase and its phase transition, as well as the effect of nonzero strangeness chemical potential on the CFL phase of dense quark matter. It is pointed out that, depending on the value of μs, both K^0 and K^-0 may condense in the CFL matter. As a function of quark chemical potential, other phases may intervene between the nuclear-matter and CFL phase. The simplest possibility, however, is a transition between nuclear and CFL matter. Such a transition could occur either at a single sharp interface or through a mixed phase region. The effect of discontinuous K^- meson condensation on the phase transition is also discussed. [
Antikaon Condensation and Hyperons Production in Protoneutron Stars
GU Jian-fa, GUO Hua, LI Xiguo, LIU Yu-xin
2005, 22(4): 429-433. doi: 10.11804/NuclPhysRev.22.04.429
Abstract(2379) PDF (213KB)(587)
Abstract:
A chiral hadronic model is extended to investigate antikaon condensation and hyperons production of protoneutron stars. Our results show that neutrino trapping makes the critical density of K^- condensation delay to higher density and K^-0 condensation not occur. Meanwhile, the equation of state (EOS) of (proto)neutron star matter considering neutrino trapping is stiffer than the case without neutrino trapping. Therefore the maximum masses of rotoneutron stars with neutrino trapping are larger than those without neutrino trapping. If hyperons are considered, antikaon condensation does not appear in (proto) neutron stars. Meanwhile, the corresponding EOS becomes much softer, and the maximum masses of (proto)neutron stars are smaller than those without hyprons.
SD-pair Shell Model Calculation of Even-even Mo Isotopes
ZHANG Rui-ping, LUO Yan-an, NING Ping-zhi, Jerry P. Draayer
2005, 22(4): 434-437. doi: 10.11804/NuclPhysRev.22.04.434
Abstract(1777) PDF (125KB)(575)
Abstract:
The SD-pair shell model was applied to study the even-even^94 Mo-^100 Mo. It is found that with the SD pair determined as 01^+ and 21^+ states of a two-valence-nucleon system with a Hamiltonian, which contains the single particle energy term and the Surface-Delta interaction (SDI) between like nucleons, the collectivity of low-lying states can be described reasonably.
Structural and Vibrational Properties of Uracil and Hydrated Uracil
WANG Zhi-ping, ZHANG Feng-shou, ZHOU Hong-yu, ZENG Xiang-hua, GU Bin, ZHANG Wei, CHENG Wei
2005, 22(4): 438-443. doi: 10.11804/NuclPhysRev.22.04.438
Abstract(2098) PDF (282KB)(552)
Abstract:
Based on an ab initio calculation and a semiempirical method, the structural and vibrational frequencies of Uracil and hydrated Uracil are studied by using the Fourier transform of velocity autocorrelation function of trajectories of molecular dynamics simulations. The finite difference harmonic method is also used to assign the vibrational frequency of each mode. It is found the calculation frequencies are in good agreement with the experiment data. The structural and vibrational frequencies of Uracil in hydrated form is discussed.
Relativistic Corrections of K-p System
WANG Wan-zhang, ZHANG Qi-ren, GAO Chong-yuan
2005, 22(4): 444-446. doi: 10.11804/NuclPhysRev.22.04.444
Abstract(2233) PDF (115KB)(528)
Abstract:
A two-body equation of the kaon-proton system with relativistic correction is derived and solved. The solution can be considered as a wave function with the probability interpretation. The scattering lengths are calculated, and the numerical result shows that the relativistic effect is apparent.