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Andrei Derevianko - One of the best experts on this subject based on the ideXlab platform.
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hyperfine structure of yb 173 toward resolving the yb 173 nuclear octupole moment puzzle
Physical Review A, 2020Co-Authors: Di Xiao, Jiguang Li 李冀光, Wesley C Campbell, Thomas Dellaert, Patrick Mcmillin, Anthony Ransford, Conrad Roman, Andrei DereviankoAbstract:The hyperfine structure (HFS) of Atomic Energy Levels arises due to interactions of Atomic electrons with a hierarchy of nuclear multipole moments, including magnetic dipole, electric quadrupole, and higher rank moments. Recently, a determination of the magnetic octupole moment of the $^{173}\mathrm{Yb}$ nucleus was reported from HFS measurements in neutral $^{173}\mathrm{Yb}$ [A. K. Singh et al., Phys. Rev. A 87, 012512 (2013)] and is four orders of magnitude larger than the nuclear theory prediction. Considering this substantial discrepancy between the spectroscopically extracted value and nuclear theory, here we propose to use an alternative system to resolve this tension---a singly charged ion of the same $^{173}\mathrm{Yb}$ isotope. Utilizing the substantial suite of tools developed around ${\mathrm{Yb}}^{+}$ for quantum information applications, we propose to extract nuclear octupole and hexadecapole moments from measuring hyperfine splittings in the extremely long-lived first excited state [$4{f}^{13}(^{2}F^{o})6{s}^{2}, J=7/2$] of $^{173}\mathrm{Yb}^{+}$. We present results of Atomic structure calculations in support of the proposed measurements.
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multipolar theory of blackbody radiation shift of Atomic Energy Levels and its implications for optical lattice clocks
Physical Review A, 2006Co-Authors: S G Porsev, Andrei DereviankoAbstract:Blackbody radiation (BBR) shifts of the {sup 3}P{sub 0}-{sup 1}S{sub 0} clock transition in the divalent atoms Mg, Ca, Sr, and Yb are evaluated. The dominant electric-dipole contributions are computed using accurate relativistic many-body techniques of Atomic structure. At room temperatures, the resulting uncertainties in the E1 BBR shifts are large and substantially affect the projected 10{sup -18} fractional accuracy of the optical-lattice-based clocks. A peculiarity of these clocks is that the characteristic BBR wavelength is comparable to the {sup 3}P fine-structure intervals. To evaluate relevant M1 and E2 contributions, a theory of multipolar BBR shifts is developed. The resulting corrections, although presently masked by the uncertainties in the E1 contribution, are required at the 10{sup -18} accuracy goal.
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multipolar theory of blackbody radiation shift of Atomic Energy Levels and its implications for optical lattice clocks
Physical Review A, 2006Co-Authors: S G Porsev, Andrei DereviankoAbstract:Blackbody radiation (BBR) shifts of the $^{3}P_{0}\text{\ensuremath{-}}^{1}S_{0}$ clock transition in the divalent atoms Mg, Ca, Sr, and Yb are evaluated. The dominant electric-dipole contributions are computed using accurate relativistic many-body techniques of Atomic structure. At room temperatures, the resulting uncertainties in the $E1$ BBR shifts are large and substantially affect the projected ${10}^{\ensuremath{-}18}$ fractional accuracy of the optical-lattice-based clocks. A peculiarity of these clocks is that the characteristic BBR wavelength is comparable to the $^{3}P$ fine-structure intervals. To evaluate relevant $M1$ and $E2$ contributions, a theory of multipolar BBR shifts is developed. The resulting corrections, although presently masked by the uncertainties in the $E1$ contribution, are required at the ${10}^{\ensuremath{-}18}$ accuracy goal.
S G Porsev - One of the best experts on this subject based on the ideXlab platform.
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multipolar theory of blackbody radiation shift of Atomic Energy Levels and its implications for optical lattice clocks
Physical Review A, 2006Co-Authors: S G Porsev, Andrei DereviankoAbstract:Blackbody radiation (BBR) shifts of the {sup 3}P{sub 0}-{sup 1}S{sub 0} clock transition in the divalent atoms Mg, Ca, Sr, and Yb are evaluated. The dominant electric-dipole contributions are computed using accurate relativistic many-body techniques of Atomic structure. At room temperatures, the resulting uncertainties in the E1 BBR shifts are large and substantially affect the projected 10{sup -18} fractional accuracy of the optical-lattice-based clocks. A peculiarity of these clocks is that the characteristic BBR wavelength is comparable to the {sup 3}P fine-structure intervals. To evaluate relevant M1 and E2 contributions, a theory of multipolar BBR shifts is developed. The resulting corrections, although presently masked by the uncertainties in the E1 contribution, are required at the 10{sup -18} accuracy goal.
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multipolar theory of blackbody radiation shift of Atomic Energy Levels and its implications for optical lattice clocks
Physical Review A, 2006Co-Authors: S G Porsev, Andrei DereviankoAbstract:Blackbody radiation (BBR) shifts of the $^{3}P_{0}\text{\ensuremath{-}}^{1}S_{0}$ clock transition in the divalent atoms Mg, Ca, Sr, and Yb are evaluated. The dominant electric-dipole contributions are computed using accurate relativistic many-body techniques of Atomic structure. At room temperatures, the resulting uncertainties in the $E1$ BBR shifts are large and substantially affect the projected ${10}^{\ensuremath{-}18}$ fractional accuracy of the optical-lattice-based clocks. A peculiarity of these clocks is that the characteristic BBR wavelength is comparable to the $^{3}P$ fine-structure intervals. To evaluate relevant $M1$ and $E2$ contributions, a theory of multipolar BBR shifts is developed. The resulting corrections, although presently masked by the uncertainties in the $E1$ contribution, are required at the ${10}^{\ensuremath{-}18}$ accuracy goal.
Haoxue Qiao - One of the best experts on this subject based on the ideXlab platform.
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the higher order blackbody radiation shift of Atomic Energy Levels
Journal of Physics B, 2017Co-Authors: Wanping Zhou, Xuesong Mei, Haoxue QiaoAbstract:The one-loop correction and two-loop contribution to black-body radiation (BBR) shift are restudied. The S-matrix approach and nonrelativistic quantum electrodynamics (NRQED) are adopted in finite temperature case. The relativistic correction to one-loop BBR-shift has a (Zα)2αT 2/m-order contribution. In the two-loop case, the pure thermal (real) photon part is too tiny to be detected; while the corrections induced by the thermal and virtual mixing diagram are at (Zα)2α2T 2/m order. We calculate the relativistic correction to one-loop BBR-shift in the ground state of hydrogen and ionized helium, which is larger than the leading term. As the leading term is proportional to T 4/Z4. We estimate these higher-order corrections may be larger than the leading term, when the system is a highly ionized (large Z) or a cold (small T ) one. a Haoxue Qiao; electronic mail: qhx@whu.edu.cn 1 ar X iv :1 60 6. 01 50 8v 6 [ ph ys ic s. at om -p h] 1 3 M ar 2 01 7
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the relativistic one loop and two loop black body radiation shift of Atomic Energy Levels
arXiv: Atomic Physics, 2016Co-Authors: Wanping Zhou, Xuesong Mei, Haoxue QiaoAbstract:The thermal relativistic one-loop and two-loop self-Energy corrections of Atomic Energy-Levels induced by the blackbody radiation(BBR) are studied. We estimated the magnitude of BBR-shift of this results in the hydrogen-like atom. The order of magnitude indicated the two loop correction of the real photon is feeble, but that thermal relativistic one-loop self-Energy correction and the thermal two-loop self-Energy corrections induced by real and virtual photon are abnormal high, which may exceed the leading order correction of BBR in the hydrogen with high $Z$ or low $T$.
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the one loop z alpha 2 alpha t 2 m and two loop z alpha 2 alpha 2 t 2 m black body radiation shift of Atomic Energy Levels
arXiv: Atomic Physics, 2016Co-Authors: Wanping Zhou, Xuesong Mei, Haoxue QiaoAbstract:The next-leading-order of the black-body radiation (BBR) shift of Atomic Energy-Levels are studied, which consists of the one-loop relativistic correction and two-loop contribution. The S-matrix approach and nonrelativistic quantum electrodynamics (NRQED) are adopted in finite temperature case. The one-loop relativistic correction has a $(Z\alpha)^{2}\alpha T^2/m$-order contribution. In the two-loop case, the pure thermal (real) photon part is finite but quite feeble so that it could be practically omitted; while the corrections induced by the thermal and virtual mixing diagram have a divergent part. We applied the renormalization procedure to obtain the finite result, which is at $(Z\alpha)^{2}\alpha^2 T^2/m$ order. Instead of being proportional to $T^4/Z^4$, as the leading term acts, these next-to-leading order corrections are depending on $(ZT)^{2}$. In this situation, the next-leading-order corrections may have larger contribution than the leading term does, when the system is a highly ionized (large $Z$) or a cold (small $T$) one.
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the higher order black body radiation shift of Atomic Energy Levels
arXiv: Atomic Physics, 2016Co-Authors: Wanping Zhou, Xuesong Mei, Haoxue QiaoAbstract:The one-loop correction and two-loop contribution to black-body radiation (BBR) shift are restudied. The S-matrix approach and nonrelativistic quantum electrodynamics (NRQED) are adopted in finite temperature case. The relativistic correction to one-loop BBR-shift has a $(Z\alpha)^{2}\alpha T^2/m$-order contribution. In the two-loop case, the pure thermal (real) photon part is too tiny to be detected; while the corrections induced by the thermal and virtual mixing diagram are at $(Z\alpha)^{2}\alpha^2 T^2/m$ order. We calculate the relativistic correction to one-loop BBR-shift in the ground state of hydrogen and ionized helium, which is larger than the leading term. As the leading term is proportional to $T^4/Z^4$. We estimate these higher-order corrections may be larger than the leading term, when the system is a highly ionized (large $Z$) or a cold (small $T$) one.
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black body radiation shift of Atomic Energy Levels the z alpha 2 alpha t 2 m correction
arXiv: Atomic Physics, 2016Co-Authors: Wanping Zhou, Xuesong Mei, Haoxue QiaoAbstract:The next-to-leading order black-body radiation(BBR) shift to Atomic Energy-Levels, namely $ (Z\alpha)^2\alpha T^2/m $ correction, was studied by using the nonrelativistic quantum electrodynamics(NRQED). We also estimate the one-loop contribution of quadrupole and the two-loop contributions of BBR-shift of the thermal(real) photon. These corrections have not been investigated before. The order of magnitude BBR-shift indicates the one-loop contribution of quadrupole is stronger than the previous result. And the two-loop contribution of BBR-shift of the thermal(real) photon is tiny, but this next-to-leading order BBR-shift may be as significant as the leading order in the multi-electron atoms or cold ones.
I P Grant - One of the best experts on this subject based on the ideXlab platform.
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new version grasp2k relativistic Atomic structure package
Computer Physics Communications, 2013Co-Authors: P Jonsson, Gediminas Gaigalas, Jacek Bieron, Charlotte Froese Fischer, I P GrantAbstract:Abstract A revised version of Grasp 2 K [P. Jonsson, X. He, C. Froese Fischer, I.P. Grant, Comput. Phys. Commun. 177 (2007) 597] is presented. It supports earlier non-block and block versions of codes as well as a new block version in which the njgraf library module [A. Bar-Shalom, M. Klapisch, Comput. Phys. Commun. 50 (1988) 375] has been replaced by the librang angular package developed by Gaigalas based on the theory of [G. Gaigalas, Z.B. Rudzikas, C. Froese Fischer, J. Phys. B: At. Mol. Phys. 30 (1997) 3747, G. Gaigalas, S. Fritzsche, I.P. Grant, Comput. Phys. Commun. 139 (2001) 263]. Tests have shown that errors encountered by njgraf do not occur with the new angular package. The three versions are denoted v1 , v2 , and v3 , respectively. In addition, in v3 , the coefficients of fractional parentage have been extended to j = 9 / 2 , making calculations feasible for the lanthanides and actinides. Changes in v2 include minor improvements. For example, the new version of rci2 may be used to compute quantum electrodynamic (QED) corrections only from selected orbitals. In v3 , a new program, jj2lsj , reports the percentage composition of the wave function in L S J and the program rLevels has been modified to report the configuration state function (CSF) with the largest coefficient of an L S J expansion. The bioscl2 and bioscl3 application programs have been modified to produce a file of transition data with one record for each transition in the same format as in Atsp 2 K [C. Froese Fischer, G. Tachiev, G. Gaigalas, M.R. Godefroid, Comput. Phys. Commun. 176 (2007) 559], which identifies each Atomic state by the total Energy and a label for the CSF with the largest expansion coefficient in L S J intermediate coupling. All versions of the codes have been adapted for 64-bit computer architecture. Program Summary Program title: Grasp 2 K , version 1_1 Catalogue identifier: ADZL_v1_1 Program summary URL: http://cpc.cs.qub.ac.uk/summaries/ADZL_v1_1.html Program obtainable from: CPC Program Library, Queen’s University, Belfast, N. Ireland Licensing provisions: Standard CPC licence, http://cpc.cs.qub.ac.uk/licence/licence.html No. of lines in distributed program, including test data, etc.: 730252 No. of bytes in distributed program, including test data, etc.: 14808872 Distribution format: tar.gz Programming language: Fortran. Computer: Intel Xeon, 2.66 GHz. Operating system: Suse, Ubuntu, and Debian Linux 64-bit. RAM: 500 MB or more Classification: 2.1. Catalogue identifier of previous version: ADZL_v1_0 Journal reference of previous version: Comput. Phys. Comm. 177 (2007) 597 Does the new version supersede the previous version?: Yes Nature of problem: Prediction of Atomic properties — Atomic Energy Levels, oscillator strengths, radiative decay rates, hyperfine structure parameters, Lande g J -factors, and specific mass shift parameters — using a multiconfiguration Dirac–Hartree–Fock approach. Solution method: The computational method is the same as in the previous Grasp 2 K [1] version except that for v3 codes the njgraf library module [2] for recoupling has been replaced by librang [3,4]. Reasons for new version: New angular libraries with improved performance are available. Also methodology for transforming from jj- to LSJ-coupling has been developed. Summary of revisions: New angular libraries where the coefficients of fractional parentage have been extended to j = 9 / 2 , making calculations feasible for the lanthanides and actinides. Inclusion of a new program jj2lsj, which reports the percentage composition of the wave function in LSJ. Transition programs have been modified to produce a file of transition data with one record for each transition in the same format as Atsp2K [C. Froese Fischer, G. Tachiev, G. Gaigalas and M.R. Godefroid, Comput. Phys. Commun. 176 (2007) 559], which identifies each Atomic state by the total Energy and a label for the CSF with the largest expansion coefficient in LSJ intermediate coupling. Updated to 64-bit architecture. A comprehensive user manual in pdf format for the program package has been added. Restrictions: The packing algorithm restricts the maximum number of orbitals to be ≤ 214 . The tables of reduced coefficients of fractional parentage used in this version are limited to subshells with j ≤ 9 / 2 [5]; occupied subshells with j > 9 / 2 are, therefore, restricted to a maximum of two electrons. Some other parameters, such as the maximum number of subshells of a CSF outside a common set of closed shells are determined by a parameter.def file that can be modified prior to compile time. Unusual features: The bioscl3 program reports transition data in the same format as in Atsp2K [6], and the data processing program tables of the latter package can be used. The tables program takes a name.lsj file, usually a concatenated file of all the .lsj transition files for a given atom or ion, and finds the Energy structure of the Levels and the multiplet transition arrays. The tables posted at the website http://atoms.vuse.vanderbilt.edu are examples of tables produced by the tables program. With the extension of coefficients of fractional parentage to j = 9 / 2 , calculations for the lanthanides and actinides become possible. Running time: CPU time required to execute test cases: 70.5 s. References: [1] P. Jonsson, X. He, C. Froese Fischer, I.P. Grant, Comput. Phys. Commun. 177 (2007) 597. [2] A. Bar-Shalom, M. Klapisch, Comput. Phys. Commun. 50 (1988) 375. [3] G. Gaigalas, Z.B. Rudzikas, C. Froese Fischer, J. Phys. B: At. Mol. Phys. 30 (1997) 3747. [4] G. Gaigalas, S. Fritzsche, I.P. Grant, Comput. Phys. Commun. 139 (2001) 263. [5] G. Gaigalas, S. Fritzsche, Z. Rudzikas, At. Data Nucl. Data Tables 76 (2000) 235. [6] C. Froese Fischer, G. Tachiev, G. Gaigalas, M.R. Godefroid, Comput. Phys. Commun. 176 (2007) 559.
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grasp92 a package for large scale relativistic Atomic structure calculations
Computer Physics Communications, 1996Co-Authors: F A Parpia, Froese C Fischer, I P GrantAbstract:We describe a suite of programs for multiconfiguration or configuration-interaction relativistic Atomic structure calculations with large configuration state function lists. Atomic orbitals are taken to be four-component spinors. Multiconfiguration self-consistent-field calculations are based on the Dirac-Coulomb Hamiltonian; at this level nuclei are assumed stationary and may be modelled either as point sources or as spherically-symmetric extended sources; in the latter case the radial variation has the form of the Fermi distribution function. Nuclear motional effects as well as the frequency-dependent transverse photon interaction may be included in configuration-interaction calculations. Oscillator strengths and radiative decay rates may be calculated. Programs are provided for the creation and manipulation of large configuration state function lists. Examples illustrate the use of the package for the prediction of Atomic Energy Levels and transition properties.
Wanping Zhou - One of the best experts on this subject based on the ideXlab platform.
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the higher order blackbody radiation shift of Atomic Energy Levels
Journal of Physics B, 2017Co-Authors: Wanping Zhou, Xuesong Mei, Haoxue QiaoAbstract:The one-loop correction and two-loop contribution to black-body radiation (BBR) shift are restudied. The S-matrix approach and nonrelativistic quantum electrodynamics (NRQED) are adopted in finite temperature case. The relativistic correction to one-loop BBR-shift has a (Zα)2αT 2/m-order contribution. In the two-loop case, the pure thermal (real) photon part is too tiny to be detected; while the corrections induced by the thermal and virtual mixing diagram are at (Zα)2α2T 2/m order. We calculate the relativistic correction to one-loop BBR-shift in the ground state of hydrogen and ionized helium, which is larger than the leading term. As the leading term is proportional to T 4/Z4. We estimate these higher-order corrections may be larger than the leading term, when the system is a highly ionized (large Z) or a cold (small T ) one. a Haoxue Qiao; electronic mail: qhx@whu.edu.cn 1 ar X iv :1 60 6. 01 50 8v 6 [ ph ys ic s. at om -p h] 1 3 M ar 2 01 7
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the relativistic one loop and two loop black body radiation shift of Atomic Energy Levels
arXiv: Atomic Physics, 2016Co-Authors: Wanping Zhou, Xuesong Mei, Haoxue QiaoAbstract:The thermal relativistic one-loop and two-loop self-Energy corrections of Atomic Energy-Levels induced by the blackbody radiation(BBR) are studied. We estimated the magnitude of BBR-shift of this results in the hydrogen-like atom. The order of magnitude indicated the two loop correction of the real photon is feeble, but that thermal relativistic one-loop self-Energy correction and the thermal two-loop self-Energy corrections induced by real and virtual photon are abnormal high, which may exceed the leading order correction of BBR in the hydrogen with high $Z$ or low $T$.
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the one loop z alpha 2 alpha t 2 m and two loop z alpha 2 alpha 2 t 2 m black body radiation shift of Atomic Energy Levels
arXiv: Atomic Physics, 2016Co-Authors: Wanping Zhou, Xuesong Mei, Haoxue QiaoAbstract:The next-leading-order of the black-body radiation (BBR) shift of Atomic Energy-Levels are studied, which consists of the one-loop relativistic correction and two-loop contribution. The S-matrix approach and nonrelativistic quantum electrodynamics (NRQED) are adopted in finite temperature case. The one-loop relativistic correction has a $(Z\alpha)^{2}\alpha T^2/m$-order contribution. In the two-loop case, the pure thermal (real) photon part is finite but quite feeble so that it could be practically omitted; while the corrections induced by the thermal and virtual mixing diagram have a divergent part. We applied the renormalization procedure to obtain the finite result, which is at $(Z\alpha)^{2}\alpha^2 T^2/m$ order. Instead of being proportional to $T^4/Z^4$, as the leading term acts, these next-to-leading order corrections are depending on $(ZT)^{2}$. In this situation, the next-leading-order corrections may have larger contribution than the leading term does, when the system is a highly ionized (large $Z$) or a cold (small $T$) one.
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the higher order black body radiation shift of Atomic Energy Levels
arXiv: Atomic Physics, 2016Co-Authors: Wanping Zhou, Xuesong Mei, Haoxue QiaoAbstract:The one-loop correction and two-loop contribution to black-body radiation (BBR) shift are restudied. The S-matrix approach and nonrelativistic quantum electrodynamics (NRQED) are adopted in finite temperature case. The relativistic correction to one-loop BBR-shift has a $(Z\alpha)^{2}\alpha T^2/m$-order contribution. In the two-loop case, the pure thermal (real) photon part is too tiny to be detected; while the corrections induced by the thermal and virtual mixing diagram are at $(Z\alpha)^{2}\alpha^2 T^2/m$ order. We calculate the relativistic correction to one-loop BBR-shift in the ground state of hydrogen and ionized helium, which is larger than the leading term. As the leading term is proportional to $T^4/Z^4$. We estimate these higher-order corrections may be larger than the leading term, when the system is a highly ionized (large $Z$) or a cold (small $T$) one.
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black body radiation shift of Atomic Energy Levels the z alpha 2 alpha t 2 m correction
arXiv: Atomic Physics, 2016Co-Authors: Wanping Zhou, Xuesong Mei, Haoxue QiaoAbstract:The next-to-leading order black-body radiation(BBR) shift to Atomic Energy-Levels, namely $ (Z\alpha)^2\alpha T^2/m $ correction, was studied by using the nonrelativistic quantum electrodynamics(NRQED). We also estimate the one-loop contribution of quadrupole and the two-loop contributions of BBR-shift of the thermal(real) photon. These corrections have not been investigated before. The order of magnitude BBR-shift indicates the one-loop contribution of quadrupole is stronger than the previous result. And the two-loop contribution of BBR-shift of the thermal(real) photon is tiny, but this next-to-leading order BBR-shift may be as significant as the leading order in the multi-electron atoms or cold ones.