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2002 Vol. 19, No. 2

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Theoretical Study on Lifetime of Metastable State 6s of Atomic Xenon
DONG Chen-zhong, XIE Lu-you, Stephan Fritzsche
2002, 19(2): 81-84. doi: 10.11804/NuclPhysRev.19.02.081
Abstract(2218) PDF (170KB)(535)
Abstract:
The recent high precision measurement on the lifetime of metastable 6s state of atomic xenon shows a difference with previous prediction by a factor of 2-3. In the present work, a new theoretical method which can systematically treat relaxation and correlation effects on the basis of the MCDF method is used to study the M2 transitions between the 5p 56s and 5p 6 configurations. By including the correlation contributions of the single and double excitations from the 5l subshells...
Fine-structure Energy Levels and Radiative Lifetime in Mo XIV
WANG Xiao-dong, JIANG Ren-bin, Pei Dong, WANG Wan-jue
2002, 19(2): 85-90. doi: 10.11804/NuclPhysRev.19.02.085
Abstract(2157) PDF (161KB)(634)
Abstract:
Energy levels, radiative lifetime and various transition parameters for allowed transitions among the 1 508 fine-structure levels belong to the (1s 22s 22p 63s 23p 6) 3d 104l, 3d 94l 2, 3d 105l, 3d 94l4m, 3d 106l, 3d 107l and so on configurations of the Cu-like ions Mo XIV have been calculated by using the expanded fully relativistic GRASP code. The results are compared with those available in the literature, and the accuracy of the present data is assessed. En...
Studies on Vibrational Structure of Diatomic Molecular States
SUN Wei-guo, HOU Shi-lin, FENG Hao, REN Wei-yi
2002, 19(2): 91-94. doi: 10.11804/NuclPhysRev.19.02.091
Abstract(2764) PDF (123KB)(640)
Abstract:
Alternative expressions for vibrational and rotational spectrum constants and energies of diatomic molecular electronic states are suggested based on the perturbation theory. An algebraic method (AM) is proposed to generate converged full vibrational spectrum from limited energy data, and a potential variational method (PVM) is suggested to produce the vibrational force constants f n s and rotational spectrum constants using the perturbation formulae and the AM vibrational constants. Applying this method...
Energy and Hyperfine Structure Studies of Excited State for Beryllium
WANG Fei, GOU Bing-cong, YU kai-zhi
2002, 19(2): 95-97. doi: 10.11804/NuclPhysRev.19.02.095
Abstract(1843) PDF (99KB)(642)
Abstract:
The Rayleigh-Ritz variational method is used with a multiconfiguration-interaction function and restricted variation method to obtain the relativistic energies of 1s 22s2p 3P o and 1s 22p 2 3Pin beryllium, including the mass polarization and relativistic corrections. Hyperfine structure is also studied to compared with theoretical and experiment data in the literature.
Hyperfine Structure Constants Calculated by Using Finite Basis Sets Constructed with B-splines
Wu Li-jin, LI Yong, GAO ke-lin
2002, 19(2): 98-102. doi: 10.11804/NuclPhysRev.19.02.098
Abstract(2697) PDF (121KB)(433)
Abstract:
The effective-operator form of many-body theory is applied to the calculation of hyperfine structure. The zeroth order hyperfine constants are evaluated with Hartree-Fock wavefunction. Τhe finite basis sets of Schrdinger s equation are constructed by using B-splines. With the finite basis sets, we have calculated the core polarization, and the correlation diagrams. The hyperfine constants of the s 1/2, p 1/2and p 3/2 states of 7Li, 23Na, 39K, 43Ca + as well as the d 3/2...
Dynamical Lie Algebra Method for Nonlinear Triatomic Molecule Potential Energy Surface
DING Shi-liang, FENG Dong-tai, ZHEN Yu-jun
2002, 19(2): 103-106. doi: 10.11804/NuclPhysRev.19.02.103
Abstract(2076) PDF (131KB)(510)
Abstract:
The algebraic Hamiltonian for a triatomic molecule can be obtained by using dynamical Lie algebra method (the expansion coefficients are obtained by fitting spectroscopic data). Triatomic molecular potential energy surface (PES) is obtained by using coherent state to take the classical limits of algebraic Hamiltonian. This PES is applied to H 2O molecule, and the deduced force constant is in good agreement with the experimental data.
Theoretical Calculation for Forbidden Transition Probability of ΔL=±2, ΔS=±1 Lines in N II
YUAN Ping, XIE Lu-you, LIU Xin-sheng, ZHANG Shu-Dong, DONG Chen-zhong
2002, 19(2): 107-109. doi: 10.11804/NuclPhysRev.19.02.107
Abstract(1723) PDF (127KB)(630)
Abstract:
The forbidden transition probabilities have been calculated for the 2p3d -2p 2 and 2p3d-2p3p(ΔL=±2, ΔS=±1) spectra of N II by using a large-scale multiconfiguration Dirac-Fock (MCDF) method. The most important effects of relativity, correlation, and relaxation are considered in the calculation Comparing with other calculations, a remarkable improvement is achieved.
Valance Electron Density of 1e1 Orbital inCyclopentane
LI Gui-qin, DENG Jing-kang, WANG Fang, ZHANG Tao, NING Chuan-gang, WANG Yan, ZHENG Yan-you
2002, 19(2): 110-112. doi: 10.11804/NuclPhysRev.19.02.110
Abstract(2190) PDF (216KB)(118)
Abstract:
The spherically averaged momentum distributions for cyclopetane have been investigated by experimental measurements and theoretical calculations. Theimpact energy is 1 200 eV plus binding energy and a symmetric non-coplanar kinematics is employed. The theoretical calculations are obtained by using Hartree-Fock method and Density Function Theory. The position density for 1e ″ 1 orbital is reported.
Study of Structure and Potential Energy Curve for Ground State X1Σ+ of LaF
CHEN Lin-hong, SHANG Ren-cheng
2002, 19(2): 113-116. doi: 10.11804/NuclPhysRev.19.02.113
Abstract(2756) PDF (138KB)(777)
Abstract:
The equilibrium geometry, harmonic frequency and dissociation energy of the molecule LaF have been calculated on several kinds of computation levels with energy-consistent relativistic effective core potentials and valence basis sets including polarization functions 4f2g and diffuse functions 1s1p1d. The possible electronic state and its reasonable dissociation limit for the ground state of LaF are determined based on Atomic and Molecular Reaction Statics(AMRS). The potential energy curve scan for...
Expanded Analysis for Spectra and Energy Levels of Mg-like Br XXIV
DU Shu-bin, JIANG Li-yang, LI Jing-wen, CHEN Hua-zhong, ZENG Xian-tang, LIU Hui-ping, MA Xin-wen, WANG You-de
2002, 19(2): 117-121. doi: 10.11804/NuclPhysRev.19.02.117
Abstract(2006) PDF (153KB)(547)
Abstract:
The spectrum of Mg-like Br, Br XXIV is investigated by means of beam-foil technique. Bromine ions of 90 and 130 MeV energy from the HI-13 tandem accelerator are used, and the wavelength region 13-29 nm is investigated. In the spectra, 24 Br XXIV transitions within the n=3 complex, i.e. between the 3s 2, 3s3p, 3p 2, 3s3d and 3p3d configurations are identifies, among them 19 have not been reported before. Based on these transition lines 19 energy levels have been determined and 14 energy level...
Lifetime Measurement for Some n=2 Levels in Be-like Sulfur
YANG Zhi-hu, MA Xin-wen, LIU Hui-ping, WANG You-de, SU Hong, XIAO Guo-qing
2002, 19(2): 122-124. doi: 10.11804/NuclPhysRev.19.02.122
Abstract(1768) PDF (109KB)(477)
Abstract:
Lifetime measurement has been carried out for some low lying n=2 levels in the four electron ions S ⅩIII by using the beam-foil technique at National Laboratory of Heavy Ion Accelerator, Lanzhoiu, China. Spectra of highly ionized sulfur obtained at an energy of 2.5 MeV/nucleon have been studied in the 190-530  wavelength range. Experimental decay curves are analysized by the CANDY program, and compared with theoretical calculations and experimental measureaments.
Study on Photodissociation Dynamics in Valence-shell Continuum Region of C2H4
ZHONG Zhi-ping, HAN Xiao-ying, LI Jia-ming
2002, 19(2): 125-127. doi: 10.11804/NuclPhysRev.19.02.125
Abstract(1897) PDF (118KB)(535)
Abstract:
The photoabsorption spectra in the valence-shell continuum region of C 2H 4 are calculated by the multi-scattering self-consistent-field method in the framework of the quantum defect theory. The energy positions of potential shape resonance are determined. The influence of the potential shape resonance on photodissociation dynamics is discussed.
Photoabsorption Spectra for Lithium Atom in Parallel Electric and Magnetic Fields
SONG Xiao-hong, LIN Sheng-lu
2002, 19(2): 128-130. doi: 10.11804/NuclPhysRev.19.02.128
Abstract(3027) PDF (107KB)(463)
Abstract:
By employing the semiclassical closed-orbit theory including core-scattering and region-splitting consistent iterative method, we calculate the closed-orbits and the recurrence spectra of n≈40, m=0 Li Rydbergatom in parallel electric and magnetic fields at scaled energy ε=-0.03. The constant scaled electric field is =0.01 . The novel spectral structures are compared with those of hydrogen obtaines by standard closed orbit theory. The effect of the core-scattering has been discussed.
Angular Distributions of K-shell Radiative Electron Capture for Bare Uranium Ions Colliding with N_2 Target
MA Xin-wen, T. Sthlker, H. F. Beyer, F. Bosch, O. Brinzanescu, C.Kozhuharov, P.H.Mokler, T. Ludziejewski, Z.Stachura, A.Warczak
2002, 19(2): 131-135. doi: 10.11804/NuclPhysRev.19.02.131
Abstract(1987) PDF (208KB)(524)
Abstract:
Radiative electron capture process occurring in high-Z ion-atom collisions studied on the heavy ion storage ring (ERS) is reviewed. The REC differential angular distributions are deduced from the X-ray spectra recorded at various observation angles for 310 and 88 MeV/u U 92+on N 2collisions, respectively. The experimental results are compared with non-relativistic and complete relativistic calculations. Deviations from sin 2θ lab are found in both cases. The contributions to near 0°observation...
High Resolution Studies of Ion Recombination with Cold Electrons
R. Schuch, N. Eklw, M. Fogle, E.Lindroth, S. Madzunkov, T. Mohamed, D. Nikolic, P.Glans, H. Danared, A. Kllberg, A. Paal
2002, 19(2): 136-139. doi: 10.11804/NuclPhysRev.19.02.136
Abstract(1726) PDF (124KB)(498)
Abstract:
We present our latest results on recombination of electrons with ions at very low energies obtained at the CRYRING heavy-ion storage ring. New data on the enhanced rate coefficient are shown. Then we concentrate on recent measurements of dielectronic recombination resonances with Li-like, Na-like, and Cu-like ions, where from the spectra of resonances very accurate values for energy splittings are derived for crucial tests of relativistic, correlation, and QED effects.
Charge Transfer Cross Sections at Low Energies and Transfer Ionization at High Energies
C.D.Lin ), Teck Lee, T.Y.Shi
2002, 19(2): 140-143. doi: 10.11804/NuclPhysRev.19.02.140
Abstract(2239) PDF (116KB)(502)
Abstract:
We report a theoretical study of state-selective differential single-electron capture cross sections between Na + and Rb(5s, 5p) atoms. The experimental data have been obtained with laser cooled target in a magnetic optical trap. We also report a theoretical study of transfer ionization of He by protons at high collision energies and analyze the transfer ionization cross section with respect to single electron capture cross section in terms of a shakeoff model.
Electron-impact Ionization of Multiply-charged Ions
K. Aichele, W. Arnold, D. Hathiramani, F. Scheuermann, E. Salzborn
2002, 19(2): 144-146. doi: 10.11804/NuclPhysRev.19.02.144
Abstract(2177) PDF (101KB)(502)
Abstract:
Electron-impact ionization of ions is one of the most fundamental processes in every kind of plasma. Especially in high-temperature plasmas-whether in laboratory (nuclear fusion) or in astrophysics (atmosphere of stars)-atoms become ionized into multiply-charged ions by electron impact. The main purpose of our investigations is to unravel the contributions from different ionization mechanisms-like direct ionization (one-step process), excitation-autoionization (two-step process) and...
Obvious Evidence of TS2 Mechanism in Ar (e, 3e) Experiment
JIA Chang-chun, A.Lahmam-Bennani, A.Duguet, L.Avaldi, M.Lecas, C.Dal Cappello
2002, 19(2): 147-149. doi: 10.11804/NuclPhysRev.19.02.147
Abstract(2103) PDF (90KB)(488)
Abstract:
Through comparing the Ar (e,3e) double ionization experimental results at low collision energy with the theoretical calculation based on the first Born approximation which include the first order mechanisms SO and TS1, the symmetry breaking about the direction of the momentum transfer shows that the non-first order effects (such as two-step 2 mechanism) play an important role.
Correction of Pressure Effect for Measurement of Differential Cross Section
ZHU Lin-fan, LIU Xiao-jing, LI Wen-bin, YUAN Zhen-sheng, CHENG Hua-dong, ZHONG Zhi-ping, XU Ke-zun
2002, 19(2): 150-152. doi: 10.11804/NuclPhysRev.19.02.150
Abstract(2178) PDF (100KB)(485)
Abstract:
The pressure effect for the measurement of differential cross section is introduced and analysed in detail. Three conclusions are obtained: the double scattered coefficient E(θ) is proportional to the strength A 0 of the excitations measured at 0°; E(θ) increases with the increasing of scattered angle; the values of E(θ) can be positive or negative. The front two conclusions are tested by experiment, and it is pointed that they are helpful to the measurement of differential cross section.
A Fully Relativistic Distorted-wave Calculation for Electron-impact Ionization Cross Section
CHEN Chong-yang, ZHAO Yong, QI Jing-bo, WANG Yan-sen
2002, 19(2): 153-156. doi: 10.11804/NuclPhysRev.19.02.153
Abstract(2024) PDF (125KB)(770)
Abstract:
A fully relativistic distorted-wave exchange approximation method is presented. It can be used to obtain electron impact ionization cross section of highly charged ions. The ionization cross sections of several H-, Li, and Ne-like ions have been calculated. Good agreement is obtained while the calculated values are compared with the experiments or other relativistic calculations.
Ionization of Sodium Dimer Na2 by Heavy Ion
WEI Bao-ren, ZHANG Feng-shou, , MA Xin-wen
2002, 19(2): 157-160. doi: 10.11804/NuclPhysRev.19.02.157
Abstract(2153) PDF (154KB)(526)
Abstract:
Based on the Time Dependent Local Density Approximation(TDLDA), the processes of excitation of sodium clusters by highly charged Ar 8+ions are simulated. The time-dependent probabilities of escaped electrons are obtained, furthermore, the ionization probabilities of the Na 2clusters are deduced.In fast ion-cluster collisions, Na 2cluster ions can be produced with minimum or even no excitation of the cluster itself
Calculations of Atomic Processes in Nlte Plasmas
WU Ze-qing
2002, 19(2): 161-164. doi: 10.11804/NuclPhysRev.19.02.161
Abstract(1609) PDF (133KB)(476)
Abstract:
The atomic processes which involves in the non-local-thermodynamic-equilibrium(NLTE) rate equations are calculated based on the first order perturbation theory. Various approximations are applied for different processes in order to reduce computer time. Comparisons are made between the present results and those of other calculations for various processes. The accuracy of the present methods is within 30%.
Dynamical Study of Competitive Model in Reaction Sr+HF→SrF+H
LIU Yu-fang, MENG Hui-yan, WANG Yong, ZHU Zun-lue, SUN Jin-feng
2002, 19(2): 165-168. doi: 10.11804/NuclPhysRev.19.02.165
Abstract(1798) PDF (144KB)(546)
Abstract:
The quasiclassical trajectory method based on the extended LEPS potential energy surface has been employed here to investigate the reaction mechanism and features in the reaction Sr+HF→SrF+H at two reactional conditions (collision energy E c o l=54.18 kJ/mol, ν=0, j=0 and E c o l=7.56 kJ/mol, ν=1, j=0). The dynamical features in the competitive reaction modes are discussed and the stationary distribution function P ν(b) of the product SrF has already been deduced...
Single Electron Detachment of Li- and Na- in Collision with He, Ne and Ar
CHEN Xi-meng, WU Cui-e, LIU Zhao-yuan, YU De-yang, QI Zhong, WANG Qiang, YANG Zhi-hu, LIU Hui-ping
2002, 19(2): 169-171. doi: 10.11804/NuclPhysRev.19.02.169
Abstract(2004) PDF (101KB)(518)
Abstract:
The count ratios R of the neutralized atoms of final state to projectiles Li -and Na -in collision with He, Ne and Ar are measured in the energy range of 3-19 keV. It is found that the count ratios R increase slowly with the collision energy in whole experimental energy range for He, Ne and Ar. For Li -→He, Ne, Ar Collisions, R(He)≈R(Ar)>R(Ne), and for Na -→He, Ne, Ar Collisions, R(He)>R(Ar)> R(Ne).
Investigation of Transfer Ionization Processes in the collisions of Partially Stripped Fluorine Ions on Neon
YU De-yang, CHEN Xi-meng, YANG Zhi-hu, WANG Qiang, LU Rong-chun, LIU Hui-ping, QI Zhong, WU Cui-e, CAI Xiao-hong, MA Xin-wen, LIU Zhao-yuan
2002, 19(2): 172-175. doi: 10.11804/NuclPhysRev.19.02.172
Abstract(1770) PDF (148KB)(621)
Abstract:
The ratios of the cross-section of the transfer ionization to the single electron capture of Neon induced by F 2+ and F 3+ ions are measured by means of the time-of-flight technologie. In the present energy range, the transfer ionization C1I1 of neon can be considered as a two-step process, in which one electron is captured by projectile and another one is directly ionized, and the transfer ionization C1I2 process should be considered as a subsequent rearrangement of neon following...
Photo-absorption Studies of Chromophores at ELISA Storage Ring
L. H. Andersen, A. Lapierre, I. B. Nielsen, S. B. Nielsen, U. V. Pedersen, S. U. Pedersen, S. Tomita
2002, 19(2): 176-179. doi: 10.11804/NuclPhysRev.19.02.176
Abstract(2085) PDF (114KB)(499)
Abstract:
Absorption of gas-phase biomolecules has been studied at the electrostatic ion storage ring ELISA. It is demonstrated that the storage ring technique with long storage times and suitable particle detection is ideal for studies of the photo-physics of chromophores. Here we discuss the absorption characteristics of the chromophores of the Green Fluorescent Protein (GFP) and compare our gas-phase absorption measurements with absorption profiles of the protein and chromophores in liquids ...
Cavity Field Spectra of Two Coupled Atoms Interacting with Nonlinear Coherent States Field
GAO Yun-feng, FENG Jian, SHI Shu-ren
2002, 19(2): 180-183. doi: 10.11804/NuclPhysRev.19.02.180
Abstract(2219) PDF (120KB)(501)
Abstract:
The cavity field spectra of two coupled atoms interacting with a radiation field are investigated. The results for the initial fields in nonlinear coherent states are calculated. The effects of dipole-dipole interaction of atoms and the Lamb-Dicke parameter of the nonlinear coherent state fields on the cavity field spectra are analyzed.
Radiative Opacity of Dense, Cold Aluminum Plasmas
ZENG Jiao-long, JIN Feng-tao, YUAN Jian-min
2002, 19(2): 184-187. doi: 10.11804/NuclPhysRev.19.02.184
Abstract(2137) PDF (130KB)(512)
Abstract:
The radiative opacity has been investigated by using detailed term accounting approximation for dense, cold aluminum plasmas under local thermodynamic equilibrium. The configuration interaction scheme has been used to obtain the relevant atomic parameters for bound-bound absorption, such as excitation energies and oscillator strengths. R-matrix method has been used to obtain the photoionization cross sections. For aluminum plasmas of density 0.36 mg/cm 3, temperature of 6-12 eV, the...
Isomerization Processes of Acetone Induced by 355 nm Laser
HU Zhan, JIN Ming-xing, LIU Hang, DING Da-jun
2002, 19(2): 188-191. doi: 10.11804/NuclPhysRev.19.02.188
Abstract(1938) PDF (136KB)(523)
Abstract:
Two isomerization processes of acetone molecule in supersonic beams induced by 355 nm laser are discussed. It is the first time to observe the isomerization from acetone to ally alcohol in this experimental condition. The isomerization process is suggested and verified by time of flight mass spectrum experiments of deuterated acetone and a transient product.
A Theoretical Study on Highly Excited States of Sc
ZHANG Xin-feng, XIA Dan, ZHONG Zhi-ping, PENG Yong-lun, XU Xiang-yuan, LI Jia-ming
2002, 19(2): 192-194. doi: 10.11804/NuclPhysRev.19.02.192
Abstract(2121) PDF (93KB)(554)
Abstract:
The energy levels of Rydberg series of Sc atom have been calculated by Relativistic Multichannel Theory (RMCT). The calculations reveal that the Rydberg spectra are complex due to the channel interactions, which is consistent with the experimental spectra.
Spatial and Temporal Behaviors of Copper Atoms and Ions in Laser-induced Plasma
LIN Hao, WU Jia-da, YING Zhi-feng, SUN Jian, XU Ning, LI Fu-ming
2002, 19(2): 195-198. doi: 10.11804/NuclPhysRev.19.02.195
Abstract(1967) PDF (153KB)(873)
Abstract:
By observing the optical emissions from copper plasma induced by laser ablationof a copper target, the dynamics of the plasma and the temporal and spatial behaviors of the plasma species are examined. The plasma is ignited from target ablation, evolves from the breakdown of the copper vapor to collisions between copper particles and energetic electrons. At the initial stage, the plasma contains large amount of copper ions and high-excited copper atoms, and then evolves to have low-energy copper...
Dynamics of Atoms in Laser Standing Wave in Regime of Immersion-lens
HE Ming, WANG Jing, ZHAN Ming-sheng
2002, 19(2): 199-201. doi: 10.11804/NuclPhysRev.19.02.199
Abstract(2149) PDF (123KB)(522)
Abstract:
The dynamics of atoms in laser standing wave (SW) in the regime of over-focused immersion-lens is studied. Through directly evolving a one-dimensional Schrdinger equation, we find that multiple focusing appears when laser intensity is larger than that required for simple focusing. If laser intensity is much higher than that for the single focusing, a "channeling" phenomenon appears, which is insensitive to the variation of some parameters, such as focal plane position and laser intensity...
Influence of Quantum Interference on Non-classical Properties of Resonance Fluorescence of a Three-level V-type Atom
GAO Shao-yan, LI Fu-li
2002, 19(2): 202-205. doi: 10.11804/NuclPhysRev.19.02.202
Abstract(1788) PDF (126KB)(563)
Abstract:
Phase-dependent squeezing spectrum and photon antibunching of resonance fluorescence from a three-level V-type atom driven by a coherent field are investigated. We show that for weak excitation intensities quantum interference can greatly enhance squeezing and change the phase quadrature at which the maximum squeezing occurs. We also notice that the maximum squeezing can appear not only in either the in-phase or the out-of-phase quadrature but also in any phase quadrature, and at which phase quadrature...
Influence of Ambient Pressure on Velocity of Emission Particle of Laser-ablated Al Target
ZHANG Shu-dong, CHEN Guan-ying, LIU Ya-nan, DONG Chen-zhong
2002, 19(2): 206-208. doi: 10.11804/NuclPhysRev.19.02.206
Abstract(1858) PDF (108KB)(710)
Abstract:
With the ambient gas pressure in the range from 8×10 -3 to 10 2 Pa, Q-switched YAG laser ablates plane aluminum target and plasma are produced. Optical emission spectroscopy is used to carry out time-resolved analysis of atomic particles. Using the resonance transition of Al I 396.1 nm (3p 2P-4s 2S), the spatiol velocity distribution of Al I has been obtained under the laser energies of 160 mJ/pulse when the ablating size is about 200 μm. The velocity is at the order of 10 6 cm/s...
AnMO Study on Methane Activation over Tetrahedral [WO4]
CHEN Hong-shan, LI Shu-ben, NIU Jian-zhong
2002, 19(2): 209-212. doi: 10.11804/NuclPhysRev.19.02.209
Abstract(2483) PDF (120KB)(523)
Abstract:
By using ab initio DFT method, the metal species formed over the silica surface on Na-W-Mn/SiO 2are optimized, the electronic structure of the catalyst and the activation process of methane is studied. The silica support in the catalyst exists as α-cristobalite and its (111) face exposes preferentially to the surface. Over the surface of α-cristobalite, tungsten existed as monografted tetrahedral \ at the optimal loading amount, and manganese exists in monografted sites or oxide clusters...
Recent Experiments on Resonant Coherent Excitation of Heavy Ions at HIMAC
Toshiyuki Azuma, T.Ito, Y.Takabayashi, C.Kondo, K.Komaki, Y.Yamazaki, E.Takada, T.Murakami
2002, 19(2): 213-217. doi: 10.11804/NuclPhysRev.19.02.213
Abstract(2368) PDF (136KB)(451)
Abstract:
When energetic ions penetrate into a crystal in a channeling condition, they travel across a periodic array of the atomic strings or ordered planes. These ions feel an oscillating field in the projectile frame. If the energy corresponding to this frequency matches with the transition energy of the electronic states of the ions, the ions have a chance to be excited. It is called Resonant Coherent Excitation (RCE). We have succeeded in observing resonant excitation of 1s electron to the n=2 states in H-like...
First-principles Study of Interaction between Molecules and a Gold Surfac
LI Hong-hai, LI Ying-de, WANG Yan-hua, WANG Chuan-kui
2002, 19(2): 218-220. doi: 10.11804/NuclPhysRev.19.02.218
Abstract(2022) PDF (107KB)(835)
Abstract:
By using density functional theory, we have investigated the interaction between a thiol-phenyl molecule (4-4′-dimercaptodibenzene) and a gold surface. The frontier orbit theory and the perturbation theory are also employed to determine quantitatively the constant of interaction energy. The results show that the bonding between the sulfur atom and the gold atoms corresponds mainly to the covalent bond and some molecular orbits are extended over the molecule and gold cluster which certainly give channels...
Calculation for Electronic Structure and Energy of Hydrogen Cluster H9
SUN Yue, GOU Qing-quan, YANG Xiang-dong
2002, 19(2): 221-223. doi: 10.11804/NuclPhysRev.19.02.221
Abstract(2181) PDF (100KB)(568)
Abstract:
The electronic structure of H 9 cluster is proposed. The total energy of this cluster is calculated by using its electron wave functions. The results are in good agreement with the value calculated by using of the modified arrangement channel quantum mechanics method in a previous paper. The results also indicate that the electronic structure of H 9 cluster is similar to that of fluorine atom.
A First Principle Study on Electronic Property of Bismuth Nanotubes
SU Chang-rong, LI Jia-Ming
2002, 19(2): 224-226. doi: 10.11804/NuclPhysRev.19.02.224
Abstract(2031) PDF (97KB)(580)
Abstract:
A first principle molecular dynamics with density functional theory and ultra-soft pseudopotential has been performed on the bismuth nanotubes. The strain energies are found to follow the classical 1/R 2 strain law. The bismuth nanotubes are expected as semi-conductor with the band gaps around 0.7 - 0.8 eV.
ab Initio Study on the Configuration of Acetone Cluster
XU Xue-song, HU Zhan, JIN Ming-xing, LIU Hang, DING Da-jun
2002, 19(2): 227-230. doi: 10.11804/NuclPhysRev.19.02.227
Abstract(2412) PDF (126KB)(828)
Abstract:
The acetone clusters are studied by ab initio calculations. HF/3-21G * method is used to optimize the configurations for all kinds of systems. B3LYP/6-31+G ** method is adopted to calculate the total energy of the systems. We also calculate the vibration frequencies in order to investigate whether the system correspondes to stable geometries. All results show that ring structure is more stable than linear structure for the acetone clusters of (CH 3COCH 3) n(n=2, 3, 4, 5).
Nonlinear Effect of Energy Loss for Swift Hydrogen Cluster Ions in Solids
YANG Chao-wen, MIAO Jing-wei, YANG Bei-fang, SHI Mian-gon, LIU Xiao-dong
2002, 19(2): 231-233. doi: 10.11804/NuclPhysRev.19.02.231
Abstract(1703) PDF (103KB)(544)
Abstract:
The energy losses of cluster ions H+2,H+3,H+4 H+5 and H+7 with energy of 260-450 keV/p in solid films have been measured. It has been found that the energy loss per proton in clusters is larger than that of single proton with the same velocity as clusters, that is, the energy ratio is larger than 1. Energy ratio increases with increasing the cluster size and velocity.
Experimental Study of H3+ Cluster
YANG Bei-fang, MIAO Jing-wei, YANG Chao-wen, SHI Mian-gon, LIU Xiao-dong
2002, 19(2): 234-237. doi: 10.11804/NuclPhysRev.19.02.234
Abstract(1987) PDF (132KB)(497)
Abstract:
The yields of H -, H, H 2, H + 2 and H + 3 for H + 3 ions passing through carbon foils have been measured respectively.The results show that the charge exchange process in the interaction of Hydrogen ions with carbon foils plays a key role in the formation of these products. The cluster effects and wake effect of H + 2 and H + 3 ions in carbon foils are also discussed.
N2 Reactivity of Positive Tungsten Cluster Ions
JIN Ming-xing, DING Da-jun, Mats Andersson, Arne Rosén
2002, 19(2): 238-241. doi: 10.11804/NuclPhysRev.19.02.238
Abstract(2848) PDF (140KB)(598)
Abstract:
A beam of tungsten clusters, seeded in He gas, is produced in a pulsed laser vaporization source. We have studied the size-dependent reactivity of positive tungsten cluster ions with N 2 under single-collision conditions by using laser-vaporization source, low-pressure reaction cell and time-of-flight mass spectrometer. The reaction probability with N 2 molecule was measured as a function of cluster size, W + 10-W + 50, for clusters produced at room temperature...
Laser-assisted Electron-atomic-hydrogen Free-free Transition
LI Shu-min, CHEN Ji, HOU Zi-fang, ZHANG Sheng-tao
2002, 19(2): 242-244. doi: 10.11804/NuclPhysRev.19.02.242
Abstract(1838) PDF (109KB)(630)
Abstract:
In the first Born approximation and the soft-photon approximation, the laser-assisted electron-atomic-hydrogen free-free transition is investigated with taking the exchange effect into acount. We find that the Kroll-Watson sum rule is significantly violated in the backward direction.
Character of Hydrogen Atom in a Strong Magnetic Field
HU Xian-quan, HU Wen-jiang, LIN Chuan-li
2002, 19(2): 245-249. doi: 10.11804/NuclPhysRev.19.02.245
Abstract(2105) PDF (148KB)(485)
Abstract:
In this paper we separate the Hamiltonian into three parts: a spherical symmetry Hamiltonian; a z-component of the angular momentum operator, and a non-spherical symmetric potential as the perturbation operator, and provide a propose method by separating the potential containing squared magnetic field B 2 into two parts: spherical symmetric and non-spherical symmetric ones so that the first-order energy correction due to the non-spherical symmetric potential is zero...
Generation of Fock States in Coupled Ladder Atom-cavity System
GONG Shang-qing, FENG Xun-li, XU Zhi-zhan
2002, 19(2): 250-252. doi: 10.11804/NuclPhysRev.19.02.250
Abstract(2057) PDF (125KB)(519)
Abstract:
The behavior of an atom-cavity system using a three-level ladder atom was investigated. It is found that, for one-mode cavity QED, a single photon can be generated via the technique of stimulated Raman adiabatic passage; for two-mode cavity QED, a two-photon pair can be generated via Stark-shift rapid adiabatic passage.
Rydberg Spectral Properties of Endohedrally Confined H Atoms Obtained by B-spline Basis Set
ZHANG Xian-zhou, JIAO Zhao-yong, RAO Jian-guo
2002, 19(2): 253-256. doi: 10.11804/NuclPhysRev.19.02.253
Abstract(1688) PDF (138KB)(491)
Abstract:
Rydberg energy levels and oscillator strength of endohedrally confined H atom have been calculated by using a nonlinear algebraic mapping technique and B-spline method.The boundary conditions are conveniently satisfied with a specially designing knot sequence.Our results show that endohedral can selectively alter the properties and energy levels of Rydberg atoms, and such atoms possess some properties and behaviours which are not previously met or studied in free systems.
A New Spectral Fitting Method and Its Application to High Order Harmonic Generation Spectra of Hydrogen in Intense Laser Field
QIAO Hao-xue, LI Bai-wen
2002, 19(2): 257-260. doi: 10.11804/NuclPhysRev.19.02.257
Abstract(2364) PDF (122KB)(581)
Abstract:
A new spectral fitting method for solving the time-dependent Schrdinger equation has been developed and applied to the atom in intense laser fields. By using this method, the time-dependent wave functions are determined with few and far between discrete mesh points. And the high accuracy wave functions with contribution of high-order-term of Δt are obtained by using Taylor series expand method. Our method is proved by computing high order harmonic generation spectra of hydrogen in laser fields...
Radiative Opacity of High Temperature Mg Plasma Calculated by DTA Model
JIN Feng-tao, ZENG Jiao-long, YUAN Jian-min
2002, 19(2): 261-264. doi: 10.11804/NuclPhysRev.19.02.261
Abstract(2313) PDF (130KB)(515)
Abstract:
The spectral resolved opacity of high temperature Mg plasma at a temperature of 56 eV and a density of 0.01 g/cm 3 is calculated by the detailed term accounting (DTA) model. Saha equation is applied to obtain the population distribution of the plasma in local thermodynamic equilibrium. Atom levels and bound-bound absorption oscillator strengths are obtained from a multi-configuration Hartree-Fock (MCHF) calculation that includes Breit-Pauli relativistic correction. After ...
Opacity Study on Dense D2, Mixtures of Hydrogen and Deuterium Plasma Generated by Shock Compression
CHEN Qi-feng, CAI Ling-cang
2002, 19(2): 265-268. doi: 10.11804/NuclPhysRev.19.02.265
Abstract(1741) PDF (129KB)(558)
Abstract:
Plasma is generated by passage of strong planar shock wave through gas. Initial experiments in deuterium and equal mol mixture of hydrogen and deuterium have been performed to produce plasma with 3.7×10 -3-7.0×10 -3 g/cm 3density. The variation of the opacity of the plasma with wavelength is measured by recording the risetime of the emitted light.
Research for Molecular Magnetic Theory
KUANG Xiao-yu, ZHOU Kang-wei, GOU Qing-quan
2002, 19(2): 269-274. doi: 10.11804/NuclPhysRev.19.02.269
Abstract(2572) PDF (218KB)(536)
Abstract:
Recently, we have established a DSF theoretical method suitable for researching molecular magnetism of the compounds consisting of transition group elements. By this method, we have revealed that the ferromagnetism of molecules is due to the cross-interaction between d orbitals of adjacent transition-metal ions, and that the antiferromagnetism is due to the parallel interactions. Further more, we have also established a magnetism theory for heterodinuclear...
odification of Brüschweiler Quantum Searching Algorithm and Realization by NMR Experiment
YANG Xiao-dong, WEI Da-xiu, LUO Jun, MIAO Xi-jia
2002, 19(2): 275-277. doi: 10.11804/NuclPhysRev.19.02.275
Abstract(2136) PDF (95KB)(599)
Abstract:
In recent years, quantum computing research has made big progress, which exploit quantum mechanical laws, such as interference, superposition and parallelism, to perform computing tasks. The most inducing thing is that the quantum computing can provide large rise to the speedup in quantum algorithm. Quantum computing can solve some problems, which are impossible or difficult for the classical computing. The problem of searching for a specific item in an unsorted database can be...
Realization of Seven-qubit Deutsch-Jozsa Algorithm on NMR Quantum Computer
WEI Da-xiu, YANG Xiao-dong, LUO Jun, SUN Xian-ping, ZENG Xi-zhi, LIU Mai-li, DING Shang-wu
2002, 19(2): 278-280. doi: 10.11804/NuclPhysRev.19.02.278
Abstract(1919) PDF (103KB)(560)
Abstract:
Recent years, remarkable progresses in experimental realization of quantum information have been made, especially based on nuclear magnetic resonance (NMR) theory. In all quantum algorithms, Deutsch-Jozsa algorithm has been widely studied. It can be realized on NMR quantum computer and also can be simplified by using the Cirac s scheme. In this paper, at first the principle of Deutsch-Jozsa quantum algorithm is analyzed, then we implement the seven-qubit Deutsch-Jozsa algorithm...
HIRFL-CSR Internal Target System
CAI Xiao-hong, LU Rong-chun, CAO Zhu-rong, YAGN Wei, MA Xin-wen, ZHAN Wen-long, D.K.Torpokov, D.Nikolenko
2002, 19(2): 281-284. doi: 10.11804/NuclPhysRev.19.02.281
Abstract(2009) PDF (166KB)(659)
Abstract:
The structure and the design of the HIRFL-CSR internal target system is reported. The HIRFL-CSR internal target can operate in two modes: cluster target mode and polarized target mode. The cluster target may provide the gas target of H 2, N 2, noble gases and small molecular gases with a density of ≥10 13 atoms/cm 2, and the polarized target may provide polarized H and D beams with a density of about 2×10 11 atoms/cm 2. The target polarization is expected to be...
Preparation for High-resolution Isotope Shift Measurements on Unstable Lithium Isotopes
H. Wang, A. Dax, G. Ewald, I. Katayama, R. Kirchner, W. N rtersh user, H. J. Kluge, T. Kühl, R. Sanchez, I. Tanihata, M. Tomaselli, C. Zimmermann
2002, 19(2): 285-289. doi: 10.11804/NuclPhysRev.19.02.285
Abstract(1990) PDF (140KB)(463)
Abstract:
A high-resolution isotope shift measurement of lithium isotopes in a suitable transition, combined with an accurate theoretical evaluation of the mass-shift contribution in the corresponding transition, can be used to determine the root-mean-square nuclear charge radii of these isotopes. For the unstable 8,9Li and the short-lived halo nucleus 11Li, this is the only approach available for obtaining nuclear-model-independent values of the charge radii within the reach of present-day facilities...
Theoretical Study of Ground-state Zero-field Splitting for ZnS∶Mn2+and ZnS∶Fe3+Systems
DIE Dong, KUANG Xiao-yu, LU Wei
2002, 19(2): 290-294. doi: 10.11804/NuclPhysRev.19.02.290
Abstract(2301) PDF (158KB)(719)
Abstract:
The EPR spectra of Mn 2+ and Fe 3+ ions in ZnS∶Mn 2+ and ZnS∶Fe 3+ systems have been extensively studied. However, the theoretical results show that the calculation values of the zero-field splitting are always much less than those of the experimental findings. Up to now, this difficulty has not yet been satisfactorily removed. In present paper, we assume that the sulfur ion has a sp 3 hybrid configuration in tetrahedral ZnS, so that the sulfur ion displays a positive...
Solution s Integrity of Intense Laser Field Schrdinger Equation and High-order Harmonic s Plateau
YANG Yu-jun, ZHU Qi-ren
2002, 19(2): 295-297. doi: 10.11804/NuclPhysRev.19.02.295
Abstract(1903) PDF (104KB)(517)
Abstract:
symmetrically splitting operator method; high-order harmonics; intense laser field;
Investigation of Valence-shell Excitations of Helium by Electron Impact
LIU Xiao-jing, ZHU Lin-fan, YUAN Zhen-sheng, LI Wen-bin, CHEN Hua-dong, XU Ke-zun
2002, 19(2): 298-300. doi: 10.11804/NuclPhysRev.19.02.298
Abstract(1887) PDF (100KB)(596)
Abstract:
With electron impact energy of 2 500 eV and energy resolution of 85 meV, the differential cross sections and the generalized oscillator strengths of the excitations of 1 1S→2 1S, 2 1P, 3 1S and 3 1P of helium has been measured by electron energy loss spectroscopy . Comparing with previous experimental and theoretical results, it seems that the first Born approximation is valid for these excitations under such an electron impact energy.