期刊文献+
共找到63篇文章
< 1 2 4 >
每页显示 20 50 100
Fine and hyperfine structures of pionic helium atoms
1
作者 白志达 钟振祥 +1 位作者 严宗朝 史庭云 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第2期236-241,共6页
The fine and hyperfine structures of pionic helium metastable states is calculated within the formalism of the Breit-Pauli Hamiltonian by using the variationally generated wave functions in Hylleraas coordinates.Our r... The fine and hyperfine structures of pionic helium metastable states is calculated within the formalism of the Breit-Pauli Hamiltonian by using the variationally generated wave functions in Hylleraas coordinates.Our results not only verify the existing values of Hori et al.[Phys.Rev.A 89,042515(2014)]for the fine structure of π^(4)He^(+),but also determine the hyperfine structure of π^(3)He^(+). 展开更多
关键词 exotic atom pionic helium fine structure hyperfine structure
下载PDF
Mixed-field effect at the hyperfine level of^(127)I^(79)Br in its rovibronic ground state:Toward field manipulation of cold molecules
2
作者 包正斌 王得富 +2 位作者 邵旭萍 黄云霞 杨晓华 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第12期312-317,共6页
The mixed-field effect at the hyperfine level of the rovibronic ground state of the^(127)I^(79)Br(X^(1)Σ,v=0,J=0)molecule is computed on the J-I uncoupled basis of|JM_(J)I_(1)M_(1)I_(2)M_(2)>,where J is the molecu... The mixed-field effect at the hyperfine level of the rovibronic ground state of the^(127)I^(79)Br(X^(1)Σ,v=0,J=0)molecule is computed on the J-I uncoupled basis of|JM_(J)I_(1)M_(1)I_(2)M_(2)>,where J is the molecular total angular momentum excluding nuclear spin,M_J is the projection number of J,I_(1) and I_(2) are the nuclear spins of the iodine and bromine atoms,and M_(1) and M_(2) are the projection numbers of I_(1) and I_(2),respectively.When the two applied electric and magnetic fields are parallel,the perturbations are rare and only one perturbation is observed in a relatively large field regime in our computation range.However,when the two fields are off-parallel,the perturbations increase significantly and some sublevels show the Feshbach-like resonance phenomenon.Therefore,such sublevels transit between weak-field seeking and strong-field seeking repeatedly,which can be utilized to enhance or suppress cold molecular collision and chemical reaction rates.Such behavior of the molecular hyperfine structure in the mixed off-parallel fields may also be utilized to construct an electric-field-assisted anti-Helmholtz magnetic trap for cold molecules and to realize evaporative cooling of cold molecules(sub-mK)into the ultracold regime(μK). 展开更多
关键词 hyperfine structure mixed Zeeman and Stark effect evaporative cooling IBr molecule
下载PDF
Local Structure Determination of Mn^(2+)-Doped Fluoride Crystals by Superhyperfine Splitting Measurements 被引量:16
3
作者 赵敏光 《Chinese Physics Letters》 SCIE CAS CSCD 1998年第1期43-45,共3页
A procedure is presented for the calculation of the Mn^(2+)-F^(-) bond length from the superhyperfine constants measured by magnetic resonance experiments.With the present technique it is possible to detect the variat... A procedure is presented for the calculation of the Mn^(2+)-F^(-) bond length from the superhyperfine constants measured by magnetic resonance experiments.With the present technique it is possible to detect the variation of the bond length,ΔR,down to 0.01Å.The technique is sensitive enough to determine the bond length R and its variationΔR experienced when pressure or temperature changes. 展开更多
关键词 hyperfine CONSTANTS BOND
下载PDF
Influence of Ti^(4+) doping on hyperfine field parameters of Mg_(0.95)Mn_(0.05)Fe_(2-2x)Ti_(2x)O_4(0≤x≤0.7)
4
作者 KUMAR S PRAKASH R +6 位作者 ALIMUDDIN CHOI H K KOO B H SONG J I CHUNG H JEONG H LEE C G 《Journal of Central South University》 SCIE EI CAS 2010年第6期1139-1143,共5页
The mixed spinel ferrite system Mg0.95Mn0.05Fe2-2xTi2xO4(0≤x≤0.7) was synthesized by the conventional solid-state reaction technique.The effect of Ti4+ doping was studied by using the Mssbauer spectroscopy measure... The mixed spinel ferrite system Mg0.95Mn0.05Fe2-2xTi2xO4(0≤x≤0.7) was synthesized by the conventional solid-state reaction technique.The effect of Ti4+ doping was studied by using the Mssbauer spectroscopy measurements at room temperature.From the analysis of the Mssbauer spectra,it is observed that s-electron density,electric field gradient(EFG),quadrupole coupling constant(QCC) and the net hyperfine magnetic fields acting on the M-ssbauer nuclei-FeA3+ and FeB3+ change with the increase of Ti4+ doping in Mg0.95Mn0.05Fe2O4.The hyperfine magnetic field decreases with the increase of Ti4+ doping. 展开更多
关键词 spinel ferrite M-ssbauer spectroscopy hyperfine magnetic field isomer shift Ti4+ doping
下载PDF
A novel method to measure the isotope shifts and hyperfine splittings of all ytterbium isotopes for a 399-nm transition
5
作者 王文丽 徐信业 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第12期174-180,共7页
We report the experimental results on measuring the isotope shifts and hyperfine splittings of all ytterbium isotopes for a 399-nm transition by using a quite simple and novel method. It benefits from the advantages o... We report the experimental results on measuring the isotope shifts and hyperfine splittings of all ytterbium isotopes for a 399-nm transition by using a quite simple and novel method. It benefits from the advantages of the modulation transfer spectroscopy in an ytterbium hollow cathode lamp and the Doppler-free spectroscopy in a collimated ytterbium atomic beam. The key technique in this experiment is simultaneously measuring the frequency separations of the two spectra twice, and the separation difference between two measurements is solely determined by the well-defined frequency of an acousto-optics modulator. Compared with the most of previously reported experimental results, ours are more accurate and completed, which will provide the useful information for developing a more accurate theoretical model to describe the interaction inside an ytterbium atom. 展开更多
关键词 isotope shift hyperfine splitting modulation transfer spectroscopy YTTERBIUM
下载PDF
Hyperfine structures and the field effects of IBr molecule in its rovibronic ground state
6
作者 王得富 邵旭萍 +2 位作者 黄云霞 李传亮 杨晓华 《Chinese Physics B》 SCIE EI CAS CSCD 2021年第11期304-308,共5页
Hyperfine structures and the field effects of IBr molecule in its rovibronic ground state are theoretically studied by diagonalizing the effective Hamiltonian matrix.Perturbations of high-J levels up to 4 are taken in... Hyperfine structures and the field effects of IBr molecule in its rovibronic ground state are theoretically studied by diagonalizing the effective Hamiltonian matrix.Perturbations of high-J levels up to 4 are taken into account when studying the hyperfine sub-levels of the J=0 level,and thus,an 80×80 matrix is constructed and solved.Some of the experimentally absent molecular constants are computed using Dalton program.Our results will be helpful in the experimental investigation of manipulation and further cooling of cold IBr molecules. 展开更多
关键词 hyperfine structure Zeeman effect Stark effect IBr molecule
下载PDF
Zeeman Effect of the Rovibronic Ground State of I35Cl at Hyperfine Level
7
作者 陈凯 胡正 +1 位作者 王庆辉 杨晓华 《Chinese Physics Letters》 SCIE CAS CSCD 2017年第10期31-33,共3页
Zeeman effect at the hyperfine level of the rovibronic ground state of I35Cl are determined on the basis of |I1JF1I2FMF| via an effective Hamiltonian matrix diagonalization method. Perturbations of the Zeeman sub- l... Zeeman effect at the hyperfine level of the rovibronic ground state of I35Cl are determined on the basis of |I1JF1I2FMF| via an effective Hamiltonian matrix diagonalization method. Perturbations of the Zeeman sub- levels are observed and the perturbation selection rules are summarized as well. Several potential applications of such Zeeman effect are suggested. 展开更多
关键词 IC Zeeman Effect of the Rovibronic Ground State of I Cl at hyperfine Level HFS
下载PDF
Hyperfine Structure of La1 in a Cathode Discharge Tube
8
作者 LUO Caiyan QU Jianan +1 位作者 ZHU Lizhou LIN Fucheng 《Chinese Physics Letters》 SCIE CAS CSCD 1991年第2期67-70,共4页
Hyperfine structures of La1 are reported using Doppler-free intermodulated fluorescence,Doppler-limited laser induced fluorescence and optogalvanic spectroscopy in a home-made cathode discharge tube.The constants A an... Hyperfine structures of La1 are reported using Doppler-free intermodulated fluorescence,Doppler-limited laser induced fluorescence and optogalvanic spectroscopy in a home-made cathode discharge tube.The constants A and B for the levels at 20197.34,21447.86cm^(-1) and constant A for the levels at 19379.40,18156.97,94910.38,and 24409.68cm^(-1) are reported.A homogeneous linewidth less than 40MHz and the different resolutions between fluorescence and optogalvanic spectroscopy were observed. 展开更多
关键词 CATHODE hyperfine STRUCTURE
下载PDF
Calculations on the hyperfine constants of the ground states for lithium-like system
9
作者 吴晓丽 俞开智 +1 位作者 苟秉聪 张孟 《Chinese Physics B》 SCIE EI CAS CSCD 2007年第8期2389-2393,共5页
In this paper a relativistic many-body perturbation calculation is performed to calculate the hyperfine constants of the ground states for lithium-like isoelectronic sequence. Zeroth-order hyperfine constants are calc... In this paper a relativistic many-body perturbation calculation is performed to calculate the hyperfine constants of the ground states for lithium-like isoelectronic sequence. Zeroth-order hyperfine constants are calculated with DiracFock wavefunctions, and the finite basis sets of the Dirac Fock equations are constructed by B splines. With the finite basis sets, the core polarization and the correlation effect are evaluated. 展开更多
关键词 hyperfine constant many-body perturbation calculation lithium-like ion
下载PDF
Theoretical study of the hyperfine interaction constants, Landé g-factors, and electric quadrupole moments for the low-lying states of the 61Niq+(q=11,12,14,and 15) ions
10
作者 张婷贤 张永慧 +1 位作者 李承斌 史庭云 《Chinese Physics B》 SCIE EI CAS CSCD 2021年第1期65-72,共8页
Highly charged nickel ions have been suggested as candidates for the ultra-precise optical clock, meanwhile the relevant experiment has been carried out. In the framework of the multiconfiguration Dirac–Hartree–Fock... Highly charged nickel ions have been suggested as candidates for the ultra-precise optical clock, meanwhile the relevant experiment has been carried out. In the framework of the multiconfiguration Dirac–Hartree–Fock(MCDHF)method, we calculated the hyperfine interaction constants, the Landég-factors, and the electric quadrupole moments for the low-lying states in the 61Ni11+,61Ni12+,61Ni14+, and61Ni15+ ions. These states are clock states of the selected clock transitions in highly charged nickel ions(see Fig. 1). Based on discussing the effects of the electron correlations, the Breit interaction, and quantum electrodynamics(QED) effect on these physical quantities, reasonable uncertainties were obtained for our calculated results. In addition, the electric quadrupole frequency shifts and the Zeeman frequency shifts of the clock transitions concerned were analyzed. 展开更多
关键词 hyperfine interaction Landég-factors electric quadrupole moment multiconfiguration Dirac-Hartree–Fock(MCDHF)method
下载PDF
Theoretical Investigation on Hyperfine Structures of Perfluoropolyether Radicals
11
作者 DONG Su-li LIU Ya-jun 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2011年第1期117-122,共6页
The geometries of CF3OCF2, CF3OCFCF3 and CF3OCF2CF2 radicals were investigated by density functional theory(DFT) method. The calculated results indicate that all the three radicals have pyramidal shapes at their cen... The geometries of CF3OCF2, CF3OCFCF3 and CF3OCF2CF2 radicals were investigated by density functional theory(DFT) method. The calculated results indicate that all the three radicals have pyramidal shapes at their centers, and the aC is one top of the pyramids. Based on the DFT optimized geometries, the hyperfine coupling constants(hfec's) of the 19F atoms of the three radicals were calculated by B3LYP, MP2(full) and QCISD(full) methods. The calculated values agree with the experimental values, especially for the a values of Fa, the a values are 125.6× 10 -4, 104.2× 10 - 4, and 83.2×10 -4 T of CF3OCF2, CF3OCFCF3 and CF3OCF2CF2, respectively. These results better explain the experimental observation. 展开更多
关键词 Perfluoropolyether radical hyperfine coupling constant Density functional theory
下载PDF
Weak- and hyperfine-interaction-induced 1s2s ~1S_0→ 1s^2 ~1S_0 E1 transition rates of He-like ions
12
作者 Laima Radziūt Erikas Gaidamauskas +3 位作者 Gediminas Gaigalas 李冀光 董晨钟 Per Jnsson 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第4期117-123,共7页
Weak- and hyperfine-interaction-induced 1 s2s 1S0→ 1S2 1 S0 E 1 transition rates for the isoelectronic sequence of Helike ions have been calculated using the multi-configuration Dirac-Hartree-Fock (MCDHF) and rela... Weak- and hyperfine-interaction-induced 1 s2s 1S0→ 1S2 1 S0 E 1 transition rates for the isoelectronic sequence of Helike ions have been calculated using the multi-configuration Dirac-Hartree-Fock (MCDHF) and relativistic configuration interaction methods. The results should be helpful for the future experimental investigations of parity non-conservation effects. 展开更多
关键词 parity non-conservation effect hyperfine interaction MCDHF method
下载PDF
Interference Effects in Hyperfine Induced 2s2p ~3P_0,~3P_2→ 2s^2~1S_0 Transitions of Be-like Ions
13
作者 李冀光 董晨钟 《Plasma Science and Technology》 SCIE EI CAS CSCD 2010年第3期364-368,共5页
In this paper, we explored the characteristics of the interference effects between perturbative states in hyperfine induced 2s2p ^3p0,^3p2→ 2s^21S0 transitions of Be-like ions. It was found that the interference effe... In this paper, we explored the characteristics of the interference effects between perturbative states in hyperfine induced 2s2p ^3p0,^3p2→ 2s^21S0 transitions of Be-like ions. It was found that the interference effects non-monotonically change with increasing atomic number Z in these two transitions. The strongest interference effect is near Z = 9 for 2s2p^3P0→2s^21S0 transition and near Z = 7 for the other. 展开更多
关键词 hyperfine induced transition Be-like ions multiconfiguration Dirac-Fock (MCDF) method
下载PDF
Stark effect of the hyperfine structure of ICl in its rovibronic ground state:Towards further molecular cooling
14
作者 王庆辉 邵旭萍 杨晓华 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第1期565-568,共4页
Hyperfine structures of IC1 in its vibronic ground state due to the nuclear spin and electric quadruple interactions are determined by diagonalizing the effective Hamiltonian matrix. Furthermore, the Stark sub-levels ... Hyperfine structures of IC1 in its vibronic ground state due to the nuclear spin and electric quadruple interactions are determined by diagonalizing the effective Hamiltonian matrix. Furthermore, the Stark sub-levels are precisely determined as well. The results are helpful for electro-static manipulation (trapping or further cooling) of cold IC1 molecules. For example, an electric field of 1000 V/cm can trap IC1 molecules less than 637μK in the lowest hyperfine level. 展开更多
关键词 hyperfine structure Stark effect
下载PDF
Investigation of the Hyperfine Structure of Atomic Niobium (Nb I) Spectral Lines Based on the Lower Energy Levels at 22936, 23010, and 23048 cm<sup>-1</sup>
15
作者 L. Windholz S. Krö ger 《Spectral Analysis Review》 2018年第2期43-52,共10页
The hyperfine (hf) structure constants of three atomic niobium energy levels in the energy range around 23000 cm-1 (at 22936.90, 23010.58, and 23048.58 cm-1) are known with only limited accuracy, and the constants of ... The hyperfine (hf) structure constants of three atomic niobium energy levels in the energy range around 23000 cm-1 (at 22936.90, 23010.58, and 23048.58 cm-1) are known with only limited accuracy, and the constants of combining levels are sometimes even unknown. Thus we performed laser spectroscopic investigations in the wavelength range between 5600 and 6500 &Aring;, and we excited altogether 16 transitions in which these lower levels are involved. Beside a more precise determination of the hf structure constants of the three lower levels (which were determined on several lines sharing a common upper level), these experiments led to the knowledge of the hf constants of nine levels with previously unknown constants. Beside these results, also the hf constants of 13 further energy levels are reported. For six of these levels, the constants were previously unknown. 展开更多
关键词 NIOBIUM hyperfine Structure hyperfine CONSTANTS Laser Spectroscopy
下载PDF
Theoretical Review of Mossbauer Effect,Hyperfine Interactions Parameters and the Valence Fluctuations in Eu Systems
16
作者 Mahmoud Abdelrazek Ahmida 《Journal of Applied Mathematics and Physics》 2019年第1期254-270,共17页
In this paper, an overview of the theory of M&#246;ssbauer effect is covered, and the main hyperfine interactions parameters which affect the shape of the resultant M&#246;ssbauer spectrum are explained and il... In this paper, an overview of the theory of M&#246;ssbauer effect is covered, and the main hyperfine interactions parameters which affect the shape of the resultant M&#246;ssbauer spectrum are explained and illustrated as well. In principle, M&#246;ssbauer effect applies to any and all nuclides, but in practice, certain ideal properties are desirable;that is, the conditions for recoil-free emission and absorption of gamma rays must be optimized. Therefore, briefly discussed in this review, one of the most commonly used for practical and fundamental studies the 151Eu M&#246;ssbauer isotope. Also, the intermediate valence phenomena and their theoretical treatments are briefly discussed. 展开更多
关键词 M?ssbauer Spectroscopy Resonant Absorption Recoil-Free Fraction 151Eu Mossbauer Isotope hyperfine Interactions Valence Fluctuations
下载PDF
Investigation and Study of the Effects of Hyperfine Interaction on the Mass of Baryons N and Δ
17
作者 Alireza Heidari Seyedali Vedad Mohammadali Ghorbani 《Journal of Modern Physics》 2012年第6期492-495,共4页
The following article has been retracted due to the investigation of complaints received against it. Mr. Mohammadali Ghorbani (corresponding author and also the last author) cheated the authors’ name: Alireza Heidari... The following article has been retracted due to the investigation of complaints received against it. Mr. Mohammadali Ghorbani (corresponding author and also the last author) cheated the authors’ name: Alireza Heidari and Seyedali Vedad. The scientific community takes a very strong view on this matter and we treat all unethical behavior such as plagiarism seriously. This paper published in Vol.3 No.6 492-495, 2012, has been removed from this site. 展开更多
关键词 BARYON SPIN ISOSPIN Schr?dinger EQUATION hyperfine Interaction
下载PDF
Effects of Hyperfine and Dopant Cation Interactions on theDC-Electrical Conductivity of MnZn Ferrites
18
作者 M.M.Abou Sekkina(Chem. Dept., Faculty of Science, Tanta University, Tanta, Egypt)A.M.El-Sayed(Inorganic Chemistry Dept., National Research Centre, Dokki, Cairo, Egypt) 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 1997年第6期467-470,共4页
Samples of undoped, and CuO, CaO, Al2O3 as well as V2O5 doped MnZn ferrite were prepared using standard ceramic method. The X-ray diffraction results for the base and doped ferrite samples show a single phase with spi... Samples of undoped, and CuO, CaO, Al2O3 as well as V2O5 doped MnZn ferrite were prepared using standard ceramic method. The X-ray diffraction results for the base and doped ferrite samples show a single phase with spinel cubic structure. The Mossbauer spectrum of the base sample indicates line broadening and overlapping due to relaxation of magnetic dipoles. The temperature dependence of DC-electrical conductivity has been discussed on the basis of electronic conduction (electron hopping) and ionic conduction mechanism. 展开更多
关键词 Effects of hyperfine and Dopant Cation Interactions on theDC-Electrical Conductivity of MnZn Ferrites
下载PDF
Observation of the hyperfine structure and anticrossings of hyperfine levels in the luminescence spectra of LiYF4:Ho3+ 被引量:1
19
作者 KIRILL N.BOLDYREV BORIS Z.MALKIN MARINA N.POPOVA 《Light(Science & Applications)》 SCIE EI CAS CSCD 2022年第9期2155-2165,共11页
Resolved hyperfine structure and narrow inhomogeneously broadened lines in the optical spectra of a rare-earth-doped crystal are favorable for the implementation of various sensors.Here,a well-resolved hyperfine struc... Resolved hyperfine structure and narrow inhomogeneously broadened lines in the optical spectra of a rare-earth-doped crystal are favorable for the implementation of various sensors.Here,a well-resolved hyperfine structure in the photoluminescence spectra of LiYF4:Ho single crystals and the anticrossings of hyperfine levels in a magnetic field are demonstrated using a self-made setup based on a Bruker 125HR high-resolution Fourier spectrometer.This is the first observation of the resolved hyperfine structure and anticrossing hyperfine levels in the luminescence spectra of a crystal.The narrowest spectral linewidth is only 0.0022 cm-1.This fact together with a large value of the magnetic g factor of several crystal-field states creates prerequisites for developing magnetic field sensors,which can be in demand in modern quantum information technology devices operating at low temperatures.Very small random lattice strains characterizing the quality of a crystal can be detected using anticrossing points. 展开更多
关键词 SPECTRA LUMINESCENCE hyperfine
原文传递
HYPERFINE INTERACTIONS IN CRYOGENIC NON-MAGNETIC AUSTENIC STEEL 30Mn23A14Cr5
20
作者 鄢晓华 陈义龙 《Chinese Science Bulletin》 SCIE EI CAS 1989年第17期1486-1488,共3页
The cryogenic non-magnetic austenic steel 30Mn23Al4Cr5 with outstanding lowtemperature physical features may be used within a large temperature range and thus has wide applied prospects, but most of the studies on thi... The cryogenic non-magnetic austenic steel 30Mn23Al4Cr5 with outstanding lowtemperature physical features may be used within a large temperature range and thus has wide applied prospects, but most of the studies on this steel focused on its macro properties.M(?)ssbauer spectroscopy is a useful tool for investigating the hyperfine interactions 展开更多
关键词 MSSBAUER spectrum hyperfine interaction electronic SPIN RELAXATION
原文传递
上一页 1 2 4 下一页 到第
使用帮助 返回顶部