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利用相对论多组态Dirac-Fock方法,系统计算了类氢离子165Ho66+, 185Re74+,187Re74+,207Pb81+, 209Bi82+, 203TI80+和205TI80+的基态超精细结构分裂以及相应的基态跃迁波长,并与相关实验数据及其它理论结果进行了对比. 相似文献
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Jørn J. Christiansen 《Journal of Molecular Spectroscopy》2005,231(2):131-136
The spectrum of cyanoformamide, NCCONH2, has been measured between 18 and 40 GHz using a Hewlett-Packard spectrometer with Stark modulation. The molecule is somewhat unstable and could most conveniently be measured in a flow system. The quadrupole hyperfine structure due to the two nitrogen nuclei has been analyzed for the ground state, and quadrupole coupling constants, rotational constants, and centrifugal distortion constants have been determined for the ground state. A rough determination of the components of the electric dipole moment was possible from the Stark shifts of suitable transitions. 相似文献
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Savukov I Matlashov A Volegov P Espy M Cooper M 《Journal of magnetic resonance (San Diego, Calif. : 1997)》2008,195(2):129-133
The precession of 3He spins is detected with ultra-low field NMR. The absolute strength of the NMR signal is accurately measured and agrees closely with theoretical calculations. The sensitivity is analyzed for applications to a neutron electric dipole moment (nEDM) fundamental symmetry experiment under development. 相似文献
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A.D. Alhaidari 《Annals of Physics》2008,323(7):1709-1728
We relax the usual diagonal constraint on the matrix representation of the eigenvalue wave equation by allowing it to be tridiagonal. This results in a larger representation space that incorporates an analytic solution for the non-central electric dipole potential cosθ/r2, which was believed not to belong to the class of exactly solvable potentials. Therefore, we were able to obtain a closed form solution of the three-dimensional time-independent Schrödinger equation for a charged particle in the field of a point electric dipole that could carry a nonzero net charge. This problem models the interaction of an electron with a molecule (neutral or ionized) that has a permanent electric dipole moment. The solution is written as a series in a basis composed of special functions that support a tridiagonal matrix representation for the angular and radial components of the wave operator. Moreover, this solution is for all energies, the discrete (for bound states) as well as the continuous (for scattering states). The expansion coefficients of the radial and angular components of the wavefunction are written in terms of orthogonal polynomials satisfying three-term recursion relations. For the Coulomb-free case, where the molecule is neutral, we calculate critical values for its dipole moment below which no electron capture is allowed. These critical values are obtained not only for the ground state, where it agrees with already known results, but also for excited states as well. 相似文献
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G. Ban K. Bodek M. Daum R. Henneck S. Heule M. Kasprzak N. Khomytov K. Kirch A. Knecht S. Kistryn P. Knowles M. Kuzniak T. Lefort O. Naviliat-Cuncic A. Pichlmaier C. Plonka G. Quémener M. Rebetez D. Rebreyend G. Rogel B. M. Sabirov M. Tur A. Weis J. Zejma 《Hyperfine Interactions》2006,172(1-3):41-43
Precision measurements of particle electric dipole moments (EDMs) provide extremely sensitive means to search for non-standard
mechanisms of T (or CP) violation. For the neutron EDM, the upper limit has been reduced by eight orders of magnitude in 50 years
thereby excluding several CP violation scenarios. We report here on a new effort aiming at improving the neutron EDM limit
by two orders of magnitude, down to a level of 3 × 10−28 e·cm. The two central elements of the approach are the use of the higher densities which will be available at the new dedicated
spallation UCN source at the Paul Scherrer Institute, and the optimization of the in-vacuum Ramsey resonance technique, with
storage chambers at room temperature, to reach new limits of sensitivity. 相似文献
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Possible future progress of the crystal-diffraction neutron electric dipole moment search experiment is discussed. A storage modification of the experiment is proposed. It is demonstrated that sensitivity of the method can be a few 10−27 e cm for the BSO crystal with the size 10×10×10 cm3 and expected luminosity of European Spallation Source (ESS). 相似文献
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A. BondarevskayaA. Prozorov L. Labzowsky G. Plunien D. Liesen F. Bosch 《Physics Reports》2011,507(1):1-42
Theoretical concepts for the production, preservation and control of polarized highly charged ion beams in storage rings are investigated. It is argued that hydrogen-like ions can be polarized efficiently by optical pumping of the Zeeman sublevels of ground state hyperfine levels and that the maximum achievable nuclear polarization exceeds 90%. In order to study the preservation of the polarization during the ion motion through the magnetic system of the ring, the concept of the instantaneous quantization axis is introduced. It is suggested that the employment of “Siberian snakes” may help to preserve the ion beam polarization in the ring. The control of the beam polarization can be achieved by different methods: by measuring the Stokes parameters for the emitted photons or by observing the angular dependence of the transition rates for polarized ions. The important motivation for the production of polarized ion beams is the possibility to observe parity nonconservation effects in the hyperfine-quenched transitions in helium-like highly charged ions, where these effects can reach an unprecedented high value for atomic physics. The possible observation of parity nonconservation effects connected with the nuclear anapole moment is also discussed. A method for the observation of the electric dipole moment of an electron in a storage ring with a polarized highly charged ion beam is proposed. This method allows, in principle, to improve the existing boundaries for the electric dipole moment of an electron. However, the requirements of the corresponding experiment are very stringent. 相似文献
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E. TangarifeC.A. Duque 《Physica B: Condensed Matter》2011,406(4):952-956
This work is concerned with the theoretical study of the combined effects of applied electric field and hydrostatic pressure on the binding energy and impurity polarizability of a donor impurity in laterally coupled double InAs/GaAs quantum-well wires. Calculations have been made in the effective mass and parabolic band approximations and using a variational method. The results are reported for different configurations of wire and barriers widths, impurity position, and electric field and hydrostatic pressure strengths. Our results show that for symmetrical structures the binding energy is an even function of the impurity position along the growth direction of the structure. Also, we found that for hydrostatic pressure strength up to 38 kbar, the binding energy increases linearly with hydrostatic pressure, while for larger values of hydrostatic pressure the binding energy has a non-linear behavior. Finally, we found that the hydrostatic pressure can increase the coupling between the two parallel quantum-well wires. 相似文献
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A.M. Ilyin E.A. Daineko G.W. Beall 《Physica E: Low-dimensional Systems and Nanostructures》2009,42(1):67-69
Computer simulation has been used to study the properties of radiation defects in a graphene sheet. Several possible stable configurations of 3D radiation defects in graphene have been simulated. Several types of absorbed species were calculated involving a single carbon atom and a dumbbell absorbed at graphene sheet surface and a dumbbell configuration at a vacancy created by radiation knocking out a carbon atom. The calculations also included the effect of structural relaxation. The defect caused by the atom being displaced from the structure converted the sheet from metallic to semiconducting. 相似文献
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Markus Spinnler Edgar R.F. Winter Raymond Viskanta 《Journal of Quantitative Spectroscopy & Radiative Transfer》2004,84(4):477-491
The objective of the paper is to model combined heat transfer in multilayer thermal insulations (MTI) for application to high-temperature fuel cells operating at temperatures higher than 650°C. Therefore, solid and gas conduction as well as radiation had to be considered. For conductive heat transfer, referenced models are subjected to sensitivity and plausibility analyses. For modelling the radiation heat transfer, a radiation scaling model reported in literature was adapted to the present problem and compared with experimental data. Finally, internal heat transfer phenomena and a numerical optimisation of MTI are discussed. 相似文献
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A systematic approach using the null-field integral equation in conjunction with the degenerate kernel is employed to solve the multiple radiation and scattering problems. Our approach can avoid calculating the principal values of singular and hypersingular integrals. Although we use the idea of null-field integral equation, we can locate the point on the real boundary thanks to the degenerate kernel. The proposed approach is seen as one kind of semi-analytical methods, since the error is attributed from the truncation of spherical harmonics. Finally, the numerical examples including one and two spheres are given to verify the validity of proposed approach. 相似文献
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Josep Batle 《Annalen der Physik》2020,532(9):2000106
Several magnetic materials consisting of dipoles owe their properties to the specific nature of the dipole–dipole interaction. In the present work, systems of particles possessing a dipole moment arranged on various types of 2D and 3D structures, completely arbitrary and, in some 2D instances, periodic (albeit finite), are studied. Noteworthy, the work is in the regime of strong dipole moments where a classical treatment is possible. The ultimate goal is to quantitatively address the unknown relation existing between the minimum possible energy of a system of dipoles and the concomitant total dipole moment. To such an end, classical numerical methods are used to the previous minimum energy–total dipole moment tandem for various magnetic configurations at zero temperature. An analytic bound for the minimal energy valid for any dimension is also obtained. With this exploration, new light is shed on the connection between the two former physical quantities, establishing an analytic inequality for particles, and describing other instances of physical interest. 相似文献
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With the idea of evaluating the dipole moment of pentafluorobenzene from a lowJ transition, its microwave spectrum was investigated in the frequency region of 8,000 to 12,400 MHz. The spectrum had been
earlier observed by the authors in the 12,400 to 18,000 MHz region which needs reassignment in the light of present investigations.
The rotational constants areA=1480·856±0·003 MHz,B=1030·066±0·003 MHz andC=607·496±0·002 MHz. The dipole moment is 1·44±0·05 D. 相似文献
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Orest Dorosh Ewa Biakowska-Jaworska Zbigniew Kisiel Lech Pszczkowski 《Journal of Molecular Spectroscopy》2007,246(2):228-232
The data available from rotational spectroscopy for chlorobenzene, bromobenzene, and iodobenzene have been extended by new measurements in the mm-wave region and in supersonic expansion in the cm-wave region. All available ground state measurements have been combined in global fits to derive precise rotational, centrifugal, and nuclear quadrupole coupling constants for the molecules. Rotational transitions in first excited states of the lowest frequency normal modes in bromobenzene and iodobenzene have been assigned and fitted. The values of electric dipole moments for 35Cl-, 79Br-, 81Br-, and I-benzene have been determined from Stark effect measurements on selected hyperfine components in the supersonic expansion spectrum, and are compared with values for several other series of monohalogen molecules. 相似文献