Hyperfine structure of the 8p 2 P 3/2 and 8p 2 P 1/2 levels of115In

The hyperfine structure of the 8p ² P _3/2 and² P _1/2 levels of¹¹⁵In was measured using high-resolution laser spectroscopy on a collimated indium atomic beam. Step-wise excitations from the metastable 5² P _3/2 state via the shortlived 6s ² S _1/2 state were employed. For the magnetic-dipole and electric-quadrupole interaction constantsa andb, respectively, the following results were obtained:a(8p ² P _3/2)=16.3 (3) MHz,b(8p ² P _3/2)=11 (3) MHz anda(8p ² P _1/2)=44.0 (5) MHz. The magnetic hyperfine structure is shown to be strongly influenced by core polarization. For the electric-quadrupole moment of¹¹⁵In the valueQ=0.79 (20) barn is deduced.     

Solution of Faddeev-type equations in the problem of two coulomb centers

The hyperfine structure of the 7p ² P _1/2,3/2 levels of¹¹⁵In and the 5p ² P _1/2 level of²⁷Al has been measured using high-resolution laser spectroscopy on atomic beams. For the magnetic-dipole and electric-quadrupole interaction constants,a andb, the following values were obtained;a(7p ² P _1/2)=90.7(10) MHz,a(7p ² P _3/2)=32.3(2) MHz andb(7p ² P _3/2)=24.5(1.5) MHz for¹¹⁵In anda(5p ² P _1/2)=20(2) MHz for²⁷Al. Many-body calculations on² P states in aluminum, gallium and indium have also been performed.     

Laser-induced fluorescence line narrowing in cobalt I

Laser-Induced Fluorescence Line Narrowing (LIFLN) measurements of hyperfine structure splittings performed on the cobalt I transition sequence3d ⁸4s a ² P _1/23d ⁷4s4p z ²4D _3/2 ⁰ 3d ⁸4s b ⁴ F _3/2are presented. The hyperfine coupling constants of theb ⁴ F _3/2 level were determined to beA = 302.8(1.9) MHz andB = – 81.6(18.2) MHz and are compared with results of both experimental and theoretical studies reported by other authors.     

Hyperfine-structure investigation in the 6s5d configuration of135Ba and137Ba

The hyperfine structure of the metastable states of the 6s5d configuration of¹³⁵Ba and¹³⁷Ba has been studied by the atomic-beam magnetic resonance (ABMR) method. The metastable barium states were populated in a plasma-discharge inside the atomic-beam oven. The atoms emerging from the ABMR-apparatus were detected by the use of a dyelaser. Compared to conventional methods this technique has the advantage of being state selective. The following magnetic dipole and electric quadrupole interaction constantsa andb have been obtained:¹³⁷Ba:a(³ D ₁)=?520.536 (3) MHzb(³ D ₁)=17.890 (3) MHza(³D₂=415.928 (3) MHzb(³D₂)=25.899 (13) MHza(³D₃)=456.559 (4) MHzb ³D₃=47.390 (16) MHz¹³⁵Ba:a ³ D ₁=?465.166 (4) MHzb(³D₁)=11.642 (4) MHza(³D₂)=371.736(4) MHzb ³ D ₂=16.745 (14) MHza(³D₃)=408.038 (6) MHzb(³D₃)=30.801 (24) MHz Using these constants and the earlier known ones for the¹ D ₂ state the hyperfine structure for the 6s5d configuration has been analyzed with an effective hyperfine hamiltonian. Hyperfine parameters obtained from the analysis have been compared with theoretical values calculated with relativistic self-consistent-field (SCF) wavefunctions. The quadrupole moments have been evaluated with the following result Q(¹³⁵Ba) =0.20(3)b and Q(¹³⁷Ba) = 0.34(4)b uncorrected for the quadrupole shielding.     

Analysis of the isotope shifts and hyperfine structure in the 3 988 Å (6s6p 1 P 1↔6s 2 1 S 0) YbI line

High-resolution laser spectroscopy using a pulsed dye-laser acting on a collimated atomic beam has been used to determine the isotope shifts in the 3 988 Å YbI line. The following results have been obtained:Δσ(176, 174)=?509(4)MHz,Δσ (174, 173)=?291(10) MHz,Δσ(174, 172)=?530(4) MHz,Δσ(172, 171)=?414(5) MHz andΔσ(172, 170)= ?665(10) MHz. The sign of the magnetic dipole interaction constant in the¹ P ₁ state for¹⁷¹Yb is found to be negative,a(¹ P ₁, 171)=?213.4(3.0) MHz. The electric quadrupole interaction constant for¹⁷³Yb in the¹ P ₁ state is found to beb(¹ P ₁, 173)=605(20) MHz.     

Redetermination of the hyperfine structure of the 6p 2 P 3/2 level in Cs133 by the zero field optical double resonance method

By combining recent level crossing data with the results from a modified atomic beam experiment by Buck, Rabi, and Senitzky in 1956, a Landég _j factor deviating about 0.6% from the LS-value ?1.3341 is obtained for the 6p ² P _3/2 level of Cs¹³³. As this large deviation is difficult to explain, a remeasurement of the hyperfine structure of this level was performed by the zero field optical double resonance method. For the magnetic dipole and the electric quadrupole interaction constantsa andb we obtain $$a(6p{}^2P_{{3 \mathord{\left/ {\vphantom {3 2}} \right. \kern-\nulldelimiterspace} 2}} ) = 50.31(5)MHz,b(6p{}^2P_{{3 \mathord{\left/ {\vphantom {3 2}} \right. \kern-\nulldelimiterspace} 2}} ) = - 0.30(33)MHz.$$ With these new values ag _j factor of ?1.3341 (15) is deduced for the 6p ² P _3/2 level of Cs¹³³, in agreement with the LS-value.     

Bestimmung der Hyperfeinstrukturaufspaltungen der Scandium-Grundzustände2 D 3/2 und2 D 5/2 und des Quadrupolmomentes des Sc45-Kernes

The hyperfine structure splittings of the electronic ground states² D _3/2 and² D _3/2 of the stable isotope Sc⁴⁵ have been measured by the atomic beam magnetic resonance method. From these splittings the magnetic dipole and electric quadrupole interaction constants are found to bea _3/2=(269,560±0,02) Mc/sb _3/2=?(26,37±0,1) Mc/sa _5/2=(109,034±0,01) Mc/sb _5/2=?(37,31±0,1) Mc/s. The values of the electric quadrupole moment calculated fromb _3/2 andb _5/2 differ by about 5% indicating that the configuration 3d 4s ² of the ground states is perturbed by higher configurations. Averaging these two values we obtain for the quadrupole moment of Sc⁴⁵ Q(Sc⁴⁵)=?(0,22±0,01) · 10^?24 cm².     

Untersuchung der Hyperfeinstruktur des 62 P 1/2-Zustandes von133Cs im starken Magnetfeld mit der optischen Doppelresonanzmethode

The hyperfine structure of the 6² P _1/2-state of¹³³Cs has been measured by optical double resonance in a strong magnetic field. From the positions of the magnetic dipole transitionsδm _J =±1,δm _I =0 theg _J -factorg _J(6² P _1/2)=0.66590(9) and the magnetic hfs-coupling constanta(6² P _1/2)=291.90(12) MHz could be derived.     

Mesure de la structure hyperfine du niveau 3s2 DE 21Ne

We describe a level-crossing measurement of the hyperfine structure of the 3s₂ level of ²¹Ne optically pumped by a laser beam. The magnetic dipole and electric quadrupole hyperfine interaction constants a and b are obtained: a = -728.0±0.8 MHz, b=-13.4±2.5 MHz.     

On the hyperfine structures of the ground state(s) in the <Superscript>6</Superscript>Li and <Superscript>7</Superscript>Li atoms

The hyperfine structure of the ground 2²S-states of the three-electron atoms and ions is investigated. By using our recent numerical values for the doublet electron density at the atomic nucleus, we determine the hyperfine structure of the ground (doublet) 2²S-state(s) in the ⁶Li and ⁷Li atoms. Our predicted values (228.2058 and 803.5581 MHz, respectively) agree well with the experimental values 228.20528(8) MHz (⁶Li) and 803.50404(48) MHz (⁷Li [R.G. Schlecht and D.W. McColm, Phys. Rev. 142, 11 (1966)]). The hyperfine structures of a number of lithium isotopes with short lifetimes, including ⁸Li, ⁹Li, and ¹¹Li atoms are also predicted. The same method is used to obtain the hyperfine structures of the three-electron ⁷Be⁺ and ⁹Be⁺ ions in their ground 2²S-states. Finally, we conclude that our approach can be generalized to describe the hyperfine structure in the triplet n³S-states of the four-electron atoms and ions.     

Elektrisches Kernquadrupolmoment von Cäsium 134

The hyperfine structure splitting of the 7² P _3/2 state of Cs¹³⁴ has been measured by optical double resonance spectroscopy in zero magnetic field. The following interaction constants have been obtained: Magnetic hfs constantA(7² P _3/2, Cs¹³⁴)=16.851 (16) MHz. Quadrupole coupling constantB(7² P _3/2, Cs¹³⁴)=18.07 (12) MHz. Then the electric quadrupole moment of Cs¹³⁴ can be calculatedQ _hfs(Cs¹³⁴)=+0.436 (3) barn without Sternheimer correction, andQ(Cs¹³⁴)=+0.356(2) barn with Sternheimer correction. A method for the production of alkali resonance cells with quantities of less than 10¹⁴ atoms of the radioactive isotope is described.     

Bestimmung derg J-Faktoren in den Zuständen 62 P 3/2 und 82 P 3/2 von133Cs

The hyperfine structures of the 6² P _3/2- and 8² P _3/2-states of¹³³Cs have been investigated by optical double resonance in a strong magnetic field. The Landé-g-factors and the hfs coupling constants were found to be:g _J(6² P _3/2)=1.3340(3)g _J(8² P _3/2)=1.3342(2)a(6² P _3/2)=50.02(25) MHza(8² P _3/2)=7.644(25) MHz. Contrarily to recent measurements, theg _J-factors agree well with the value calculated from the Landé formula.     

Die Hyperfeinstruktur des 32P3/2-Zustands von Natrium im starken Magnetfeld

The hyperfine structure of the 3²P_3/2 State of Na²³has been measured by the optical double resonance technique in a magnetic field of 3.1 kG sufficiently strong to decouple completelyI andJ. In the case of π or (σ⁺+σ^?) excitation the double resonance signal represents the superposition curve of eight unresolved radio-frequency transitions. The dependence of the signal on the pressure of sodium vapour and the radio-frequency field strength has been studied. The analysis of the experimental curves yields for the hyperfine coupling constants the valuesa=(18.7±0.4) Mc/s andb=(3.4±0.4) Mc/s. The nuclear electric quadrupole moment derived from the ratio ofb/a isQ=(0.146±0.02) · 10^?24cm². The Lande factor and the lifetime for the 3²P_3/2state are g_J=1.3344±0.0004 and τ=(1.61±0.07) · 10^?8 sec.     

Messung der Hyperfeinstrukturaufspaltung des4F9/2-Grundzustandes im Co59-I-Spektrum und Bestimmung des Quadrupolmomentes des Co59-Kernes

The hyperfine structure splittings of the electronic ground statea ⁴ F _9/2 in the Co⁵⁹-I-spectrum have been measured with a magnetic atomic-beam resonance-apparatus. From these splittings the magnetic dipole and electric quadrupole interaction constants are found to beA (a ⁴ F _/2)=(450,284±0,01) Mc/sec,B (a ⁴ F _9/2)= (139,63±0,5) Mc/sec. Taking into account the mixture of thea ⁴ F _9/2 state with states of the same 3d ⁷ 4s ²-electron-configuration, an electric quadrupole moment of Co⁵⁹ ofQ=(0,404±0,04) 10^?24 cm² was obtained. No Sternheimer-correction has been included.     

Levelcrossing experiments in the first excited1 P 1 states of the alkaline earths

The hyperfine structure of the lowest¹P₁ state of²⁵Mg,⁴³Ca,⁸⁷Sr,¹³⁵Ba and¹³⁷Ba have been measured by the level-crossing and anticrossing technique. The magnetic dipole and electric quadrupole coupling constants determined by these measurements are²⁵Mg(3s3p¹P₁):A=? 7.7(5) MHz; 16 MHz>B>0 MHz,⁴³Ca(4s4p¹P₁):A=? 15.3(4) MHz; ¦B¦<12 MHz,⁸⁷Sr (5s5p¹P₁:A=? 3.4(4) MHz;B=39(4) MHz,¹³⁵Ba(6s6p¹P₁):A=? 97.5(1.0) MHz;B=31(9)MHz,¹³⁷Ba(6s6p¹P₁):A=?109.2(1.2) MHz;B=51(12)MHz. The results have been compared with the predictions of the Breit-Wills theory of the two-electron hyperfine structure using the experimental data on the³P states. Large discrepancies have been observed which are due to different radial wave functions of thes andp electron in the triplet and singlet system. This effect has been taken into account by fitting the data with the aid of two additional parameters. That this procedure is justified is shown by an analysis of the fine structure splitting, the life times, and the isotopic shifts in thesp configurations of group II elements.     

Die Hyperfeinstruktur des 32 P 1/2-Zustandes von Natrium im starken Magnetfeld

The hyperfine structure of the 3² P _1/2-state of²³Na has been measured by the optical double resonance technique in a magnetic field sufficiently strong to decoubleI andJ. The magnetic interaction constantA _1/2 and the Landég-factor were found to be:A _1/2=94.3(2) MHz,g=0.66581(12).     

Bestimmung der Kernmomente des Ho165 aus der Hyperfeinstruktur des Grundzustandes im Ho I-Spektrum

In an atomic beam magnetic resonance experiment, the hyperfine interaction constantsA andB of the⁴ I _2/15-groundstate of Ho¹⁶⁵ were found to beA=800,58389 (50) MHz,B=?1667,997 (50) MHz. Using an effective value for 〈r ^?3〉, the magnetic moment of the Ho¹⁶⁵ nucleus was calculated to beμ=4·1(4)μ _n . The quadrupolement was determined by use of the 〈r ^?3〉 given byWatson andFreeman. The result isQ=2·4·10^?24 cm².     

On the possibility to determine weak hyperfine structure interaction constants by magnetic depolarization

A new method to measure weak hyperfine structure interaction constants (aτ ? 1) by magnetic depolarization, involving interaction between nuclear orientation and electronic alignment, was used on the 3 ¹P₁ level of ³He. It was found that a/Γ = 0.075 ± 0.010.     

Atomic beam magnetic resonance investigations in the 2p 2 3 P ground multiplet of the stable carbon isotopes12C and13C

The hyperfine structure seperations Δv andg _J -factors have been measured in the 2p ^{2 3} P states of¹³C(I=1/2) and¹²C(I=0), respectively, using the atomic beam magnetic resonance method. The results are Δv(³ P ₁,¹³C)=4.200 (25) MHz, Δv(³ P ₂,¹³C)=372.593 (25) MHz,g _J (³ P ₁,¹²C)=1.501052 (13), andg _J (³ P ₂,¹²C)=1.501039 (15). After applying corrections due to perturbations by neighbouring fine structure levels one deduces the constants of the magnetic dipole interactionA(³ P ₁,¹³C)=+2.838 (17) MHz, A(³ P ₂,¹³C)=+149.055 (10) MHz. No signs of theA-factors were determined by the experiment; they follow from the known positive sign of the nuclear magnetic moment μ _I of¹³C. CombiningA(³ P ₂,¹³C) with the results of other measurements on¹¹C, yields μ _I (¹¹C)=?0.964 (1) nm.