Ab-initio calculations of pair-correlation effects on the hyperfine structure of the 4s 4p and 4s 3d configurations of Ca

The hyperfine structure of the 4s 4p and 4s 3d configurations of Ca has been evaluated using many-body perturbation theory. Single excitations and pair-correlation effects have been included by solving coupled one-particle and two-particle differential equations numerically. The correlation between the valence electrons has been treated selfconsistently by solving these equations iteratively for the valence pair. Core-polarisation effects have been evaluated by hyperfine-induced single-particle functions. From the calculated and experimental results of the two configurations,Q=?49(5) mb has been evaluated for the nuclear quadrupole moment of⁴³Ca.     

Fine and hyperfine structure of the 22 P term of7Li; determination of the nuclear quadrupole moment

Microwave transitions between the Zeeman split doublet states 2² P _1/2 and 2² P _3/2 of⁷Li have been measured using the optical double resonance method. The fine structure separation was determined to bev _fs=10.053.184(58) MHz. The hyperfine structure was well resolved and led to considerably improved precision of the diagonal coupling constantsa _1/2=45.914(25) MHz,a _3/2=?3.055(14) MHz,b=?0.221(29) MHz. Furthermore, the contact, spin dipolar and orbital magnetic hyperfine constants are evaluated using additional results from level crossing experiments, which are more sensitive on the non-diagonal magnetic hyperfine constanta _3/2,1/2. The results are in good agreement with recent theoretical calculations. The nuclear quadrupole moment is derived fromb to beQ(⁷Li)=?41(6) mbarn.     

Laser-rf double-resonance hyperfine structure measurements of the metastable 3d 4s 1 D 2 state of43Ca

The hyperfine structure of the (3(d 4s)¹ D ₂metastable state of⁴³Ca has been measured using theABMR-LIRF method (atomic beam magnetic resonance, detected by laser induced resonance fluorescence). The measurements yielded for the magnetic dipole and electric quadrupole constantsA=?17.650(2) MHz andB=?4.642(12) MHz, respectively. From the measuredB factor the spectroscopic electric quadrupole moment (uncorrected for shielding effects) has been calculated to beQ(⁴³Ca)=?0.062(12) barn. In addition, isotope shifts in the lines (3d 4s)¹ D ₂(3d 4p)¹ F ₃ ⁰ and (3d 4s)¹ D ₂(4s 5p)¹ p ₁ ⁰ for the stable calcium isotopes have been obtained by high resolution laser spectroscopy.     

Ground-State hyperfine structure and nuclear magnetic moment of Thulium-169

The hyperfine structure of the 4f ¹³ 6s ^{2 2} F _7/2 ground state of Tm¹⁶⁹ has been studied with the atomic beam magnetic resonance method. By measuring strongly field-dependent transitions in external magnetic fields between 2200 and 3000 Gauss the interaction between the nuclear magnetic dipole momentμ _I and the external field was determined. These measurements yielded a direct value forμ _I independent of the electronic properties of the Tm-atom. The results are:μ _I=? 0.2310 (15)μ _n (diamagnetically corrected), magnetic dipole interaction constanta=? 374.137661(3) Mc/sec andg _J(4f ¹³ 6s ^{2 2} F _7/2)=1.141189 (3).     

The hyperfine quadrupole moment of muonium in the ground state

The quadrupole moment of the ground state of the μ⁺e^? atom is calculated to be (3m_em_μ)^?1; effects in a crystal are briefly discussed.     

Isotope shift and hyperfine structure of43Ca by laser spectroscopy

The isotope shift⁴⁰Ca-⁴³Ca in the 4s ^{2 1} S ₀-4s4p ³ P ₁ intercombination line as well as the hyperfine structure splitting of the 4s4p ³ P ₁ state of⁴³Ca have been remeasured by saturation spectroscopy with a tunable stabilizedcw dye laser and an atomic beam of natural Ca as absorber. The nuclear charge radius of⁴³Ca obtained here reconciles our result with the radius obtained from measurements in muonic Ca-atoms and in the Ca resonance line. It reconfirms the fact that the charge radius of⁴³Ca is considerably smaller than the ones of both neighbouring even isotopes. The discrepancy of our previous measurement for this charge radius was due to a wrong assignment of so far unobserved absorption lines of probably molecular origin occuring in the neighbourhood of the atomic resonances under study.     

Hyperfine structure in the Gd II spectrum and the nuclear electric quadrupole moment of157Gd

The hyperfine structure of¹⁵⁷Gd was investigated in 20 Gd II lines by means of a photoelectric recording Fabry-Perot interferometer with digital data processing. The hyperfine splitting factors,A andB, were obtained by computer fits to the observed line structures. Using a multiconfigurational set of wave functions in intermediate coupling derived by Wyart, mono-electronic hyperfine parameters were deduced by a parametric treatment. The nuclear electric quadrupole moment of¹⁵⁷Gd was evaluated from the quadrupole interaction of the 5d electron in 4f ⁷ 5d6s, the 5d electron in 4f ⁷ 5d6p, and the 6p electron in 4f ⁷ 5d6p. The three values obtained for the quadrupole moment agree very well. The final result, corrected for Sternheimer shielding, isQ(¹⁵⁷Gd) =1.34(7)·10^?24 cm².     

Reinvestigation of the quadrupole hyperfine structure in rotational spectra of chloroiodomethane

The b-type Q-branch transitions of chloroiodomethane were remeasured and the quadrupole hyperfine structures were reinvestigated by a new method to improve the discrepancies in the hyperfine spectra observed and calculated in a previous work. The χ values of the off-diagonal element of ³⁵Cl and ³⁷Cl were determined. The nuclear quadrupole coupling constants were revised to be χ_aa = −1421.9 ± 1.9, χ_bb = 392.6 ± 1.0, χ_cc = 1029.3 ± 2.1, and {χ_ab} = 1174.9 ± 1.7 MHz of iodine; χ_aa = −31.1 ± 1.1, χ_bb = −9.0 ± 0.6, χ_cc = 40.1 ± 1.2, and {χ_ab} = 53.6 ± 4.2 MHz of ³⁵Cl for ³⁵Cl species; χ_aa = −1418.4 ± 2.5, χ_bb = 386.5 ± 2.7, χ_cc = 1031.9 ± 3.6, and {χ_ab} = 1181.8 ± 1.7 MHz of iodine; and χ_aa = −21.1 ± 1.7, χ_bb = −8.5 ± 0.9, χ_cc = 29.6 ± 1.9, and {χ_ab} = 34.6 ± 1.4 MHz of ³⁷Cl for ³⁷Cl species, respectively.     

Microwave spectrum,quadrupole hyperfine interaction,and electric dipole moment of the BrF molecule

The measurements of the microwave spectrum of BrF were carried out on the hyperfine components of J = 1 ← 0 and J = 2 ← 1 rotational transitions of ⁷⁹BrF and ⁸¹BrF. A direct diagonalization procedure of the energy matrix of the total Hamiltonian including Stark effect has been used. The following constants were derived:

     

11.

Reinvestigation of the quadrupole hyperfine structure in rotational spectra of 3-lodopropene     

Ichiro Ohkoshi  Yuzuru Niide  Mitsuru Takano  Yoshiaki Sasada 《Journal of Molecular Spectroscopy》1980,82(1):27-34

Quadrupole hyperfine structure of 3-iodopropene has been reinvestigated by the use of two methods, (1) Two-Level Approximation, and (2) Direct Solution of the Energy Matrix, to improve the discrepancies between the observed and calculated hyperfine spectra reported in a previous work (J. Mol. Spectrosc.66, 421–427 (1977)). Appreciable improvement can be found in the discrepancies between the observed and calculated spectra. By means of these two methods, the χ values of CH₂ICHCH₂ have been revised to be: |χ_ab| = 1160 MHz and χ_zz = ?1920 MHz, respectively.     

12.

New energy levels and transitions for the 4s4p5p configuration in Kr VI     

E.E. Farias  M. Raineri  J. Reyna Almandos  F.O. Borges 《Journal of Quantitative Spectroscopy & Radiative Transfer》2011,112(15):2463-2468

The spectrum of five-time ionized krypton, Kr VI, was recorded in the 240-2600 Å wavelength range, resulting in 61 new classified lines as transitions between levels of configurations 4p³, 4s²5p, 4s4p4d, 4s4p5s and 4s4p5p. All the 18 energy levels belonging to 4s4p5p configuration except one were determined. Eight new energy level values corresponding to configurations 4s4p4f and 4p24d, supported by 26 new classified lines were also determined and used in the interpretation of the observed 4s4p5p configuration. The experimental data were obtained from a capillary-discharge tube and theta pinch light sources. Multiconfiguration Hartree-Fock calculations with relativistic corrections and a least-squares fitted parametric calculation has been carried out.     

13.

Molecular structure, nuclear quadrupole coupling constant and dipole moment of nitrogen trichloride from microwave spectroscopy     

G. Cazzoli  P. G. Favero  A. Dal Borgo   《Journal of Molecular Spectroscopy》1974,50(1-3)

The rotational constants of four isotopic species of nitrogen trichloride have been obtained from transitions in the millimeter region. Two r_s structures have been obtained with the following average values of the parameters. rN−C1=1.7535 ± 0.0020 A.The Stark effect of the J = 3 ← 2 transition was analyzed to obtaine the value 0.39 ± 0.01 D for the dipole moment of NCl₃. The measurement of the separation of the two strongest hyperfine components of the J = 2 ← 1 transition yielded the value of −108 ± 3 MHz for the N---Cl bond axis quadrupole coupling constant.     

14.

Electronic structure of arsabenzene: Microwave spectrum,dipole moment,and nuclear quadrupole coupling constants     

Robert P. Lattimer  Robert L. Kuczkowski  Arthur J. Ashe  A.L. Meinzer 《Journal of Molecular Spectroscopy》1975,57(3):428-435

The microwave spectrum of arsabenzene was analyzed; a dipole transitions were observed. The following rotational constants were obtained; A = 4871.03 ± 0.18 MHz, B = 2295.87 ± 0.01 MHz, C = 1560.10 ± 0.01 MHz. The dipole moment was 1.10 ± 0.04 D. The nuclear quadrupole coupling constants due to the ⁷⁵As nucleus were χ_aa = ?186.4 ± 0.1 MHz, χ_bb = 43.5 ± 0.2 MHz, χ_cc = 142.9 ± 0.2 MHz, and the asymmetry parameter, η = 0.533 ± 0.002. Analysis of the quadrupole coupling constants indicated that the population of the 4p orbitals on arsenic decrease in the order n_a > n_b > n_c.     

15.

Nuclear electric quadrupole moment of41Ca by laser-RF spectroscopy     

Arnold  M.  Kowalski  J.  Stehlin  T.  Träger  F.  zu Putlitz  G. 《Zeitschrift für Physik A Hadrons and Nuclei》1983,314(3):303-307

Zeitschrift für Physik A Hadrons and nuclei - The nuclear electric quadrupole moment of41Ca, which contains a single neutron outside closed proton and neutron shells (N=Z=20) has been...     

16.

Recent hyperfine structure investigations in the configurations 4f 136s 2, 4f 136s6p,and 4f 125d6s 2 of Tm I     

H. -W. Brandt  P. Camus 《Zeitschrift für Physik A Hadrons and Nuclei》1977,283(4):309-313

By use of optical hyperfine structure investigations in the Tm I spectrum theA- values of 20 levels of the configurations 4f ¹³ 6s 6p and 4f ¹² 5d 6s ² and theA-value of 4f ¹³ 6s ^{2 2} F _5/2 were determined very accurately. These data and tenA-factors from former experiments are used for theoretical calculations. 30A-factors have been interpolated from intermediate coupling wave functions using 9 effective mono-electronic parameters. The r.m.s. deviation between experimental and theoreticalA- values amounts to 0.5 10^?3 cm^?1 and represents 3/100 of the average value of the measuredA-factors.     

17.

Observation of quadrupole and dipole diamagnetic shifts in atomic ground-state hyperfine structure     

Lipson SJ  Fletcher GD  Larson DJ 《Physical review letters》1986,57(5):567-570

     

18.

The Sachs moment and finite size effects in muonic hyperfine structure     

K. Schäfer 《Nuclear Physics A》1975,249(3):523-532

In calculations of finite size effect in muonic hyperfine structure, the meson exchange part of nuclear magnetism has so far not been taken explicitly into account. We investigate this effect for the Sachs moment and show that the reduction factor is approximately the same as for the orbital part. Consequences for theoretical values of the h.f.s. constant A₁ are discussed for the special nucleus ²⁰⁹Bi.     

19.

Extraction of hyperfine anomalies without precise values of the nuclear magnetic dipole moment     

J.R. Persson 《The European Physical Journal A - Hadrons and Nuclei》1998,2(1):3-4

A new method for extracting the hyperfine anomaly from experimental hyperfine structure constants is suggested. Instead of independent high-precision measurements of the nuclear magnetic dipole moment, precise measurements of magnetic dipole hyperfine interaction constants for two atomic states and a theoretical analysis can be used. This can lead to determination of hyperfine anomaly for radioactive isotopes where the nuclear magnetic dipole moment is not known with high accuracy. Received: 17 February 1998     

20.

Quadrupole moment of muonium and hyperfine structure of muonium levels in silicon     

V.G. Baryshevskii  S.A. Kuten  V.I. Rapoport 《Physics letters. A》1982,88(6):289-291

It is shown that experimental data on Mu¹ in silicon are most satisfactorily described by the uniaxial symmetric spin hamiltonian which means muonium displacement from the octa-cell center.     

79BrF

81BrF

Be (MHz) 10 667.610 (60)

10 616.522 (70)

eq0Q (MHz) 1086.80 (30)

908.09 (20)

eq1Q (MHz) 1085.66 (60)

907.41

Reinvestigation of the quadrupole hyperfine structure in rotational spectra of 3-lodopropene

Quadrupole hyperfine structure of 3-iodopropene has been reinvestigated by the use of two methods, (1) Two-Level Approximation, and (2) Direct Solution of the Energy Matrix, to improve the discrepancies between the observed and calculated hyperfine spectra reported in a previous work (J. Mol. Spectrosc.66, 421–427 (1977)). Appreciable improvement can be found in the discrepancies between the observed and calculated spectra. By means of these two methods, the χ values of CH₂ICHCH₂ have been revised to be: |χ_ab| = 1160 MHz and χ_zz = ?1920 MHz, respectively.     

New energy levels and transitions for the 4s4p5p configuration in Kr VI

The spectrum of five-time ionized krypton, Kr VI, was recorded in the 240-2600 Å wavelength range, resulting in 61 new classified lines as transitions between levels of configurations 4p³, 4s²5p, 4s4p4d, 4s4p5s and 4s4p5p. All the 18 energy levels belonging to 4s4p5p configuration except one were determined. Eight new energy level values corresponding to configurations 4s4p4f and 4p24d, supported by 26 new classified lines were also determined and used in the interpretation of the observed 4s4p5p configuration. The experimental data were obtained from a capillary-discharge tube and theta pinch light sources. Multiconfiguration Hartree-Fock calculations with relativistic corrections and a least-squares fitted parametric calculation has been carried out.     

Molecular structure, nuclear quadrupole coupling constant and dipole moment of nitrogen trichloride from microwave spectroscopy

The rotational constants of four isotopic species of nitrogen trichloride have been obtained from transitions in the millimeter region. Two r_s structures have been obtained with the following average values of the parameters. rN−C1=1.7535 ± 0.0020 A.The Stark effect of the J = 3 ← 2 transition was analyzed to obtaine the value 0.39 ± 0.01 D for the dipole moment of NCl₃. The measurement of the separation of the two strongest hyperfine components of the J = 2 ← 1 transition yielded the value of −108 ± 3 MHz for the N---Cl bond axis quadrupole coupling constant.     

Electronic structure of arsabenzene: Microwave spectrum,dipole moment,and nuclear quadrupole coupling constants

The microwave spectrum of arsabenzene was analyzed; a dipole transitions were observed. The following rotational constants were obtained; A = 4871.03 ± 0.18 MHz, B = 2295.87 ± 0.01 MHz, C = 1560.10 ± 0.01 MHz. The dipole moment was 1.10 ± 0.04 D. The nuclear quadrupole coupling constants due to the ⁷⁵As nucleus were χ_aa = ?186.4 ± 0.1 MHz, χ_bb = 43.5 ± 0.2 MHz, χ_cc = 142.9 ± 0.2 MHz, and the asymmetry parameter, η = 0.533 ± 0.002. Analysis of the quadrupole coupling constants indicated that the population of the 4p orbitals on arsenic decrease in the order n_a > n_b > n_c.     

Nuclear electric quadrupole moment of41Ca by laser-RF spectroscopy

Zeitschrift für Physik A Hadrons and nuclei - The nuclear electric quadrupole moment of41Ca, which contains a single neutron outside closed proton and neutron shells (N=Z=20) has been...     

Recent hyperfine structure investigations in the configurations 4f 136s 2, 4f 136s6p,and 4f 125d6s 2 of Tm I

By use of optical hyperfine structure investigations in the Tm I spectrum theA- values of 20 levels of the configurations 4f ¹³ 6s 6p and 4f ¹² 5d 6s ² and theA-value of 4f ¹³ 6s ^{2 2} F _5/2 were determined very accurately. These data and tenA-factors from former experiments are used for theoretical calculations. 30A-factors have been interpolated from intermediate coupling wave functions using 9 effective mono-electronic parameters. The r.m.s. deviation between experimental and theoreticalA- values amounts to 0.5 10^?3 cm^?1 and represents 3/100 of the average value of the measuredA-factors.     

The Sachs moment and finite size effects in muonic hyperfine structure

In calculations of finite size effect in muonic hyperfine structure, the meson exchange part of nuclear magnetism has so far not been taken explicitly into account. We investigate this effect for the Sachs moment and show that the reduction factor is approximately the same as for the orbital part. Consequences for theoretical values of the h.f.s. constant A₁ are discussed for the special nucleus ²⁰⁹Bi.     

Extraction of hyperfine anomalies without precise values of the nuclear magnetic dipole moment

A new method for extracting the hyperfine anomaly from experimental hyperfine structure constants is suggested. Instead of independent high-precision measurements of the nuclear magnetic dipole moment, precise measurements of magnetic dipole hyperfine interaction constants for two atomic states and a theoretical analysis can be used. This can lead to determination of hyperfine anomaly for radioactive isotopes where the nuclear magnetic dipole moment is not known with high accuracy. Received: 17 February 1998     

Quadrupole moment of muonium and hyperfine structure of muonium levels in silicon

It is shown that experimental data on Mu¹ in silicon are most satisfactorily described by the uniaxial symmetric spin hamiltonian which means muonium displacement from the octa-cell center.