Atomic Beam Magnetic Resonance Method Research Articles

Hyperfine structure of seven atomic levels of91Zr and the91Zr nuclear electric quadrupole moment

The hyperfine structure of the low-lying atomic levels 4d2 5s23F2, 3, 4 and 4d3 5s5F2, 3, 4, 5 of91Zr has been studied using the atomic-beam magnetic-resonance method. Using intermediate coupling wave functions derived for the configurations (4d+5s)4 the experimental data are analysed with respect to the effective operator formalism. The effective radial parameters of the magnetic dipole and electric quadrupole interaction are determined for the two configurations 4d2 5s2 and 4d3 5s and are compared with relativistic calculations. The value obtained for the electric quadrupole moment of the91Zr nuclear ground state isQ=− 0.21(2) barn (uncorrected for core polarization effects).

Hyperfine structure measurements in metastable atomic states — nuclear spins of 201Pb and 203Pb

A new atomic-beam source has been used to populate metasbable states within the atomic ground-state configuration for lead. With this source and the atomic-beam magnetic resonance method, hyperfine structure measurements have been performed in metastable states to determine the nuclear ground-state spins of two lead isotopes as 203 Pb(I = 5 2 ) , 201 Pb(I = 5 2 ) .

Hyperfine structure of the 5d 26s 23F 3,4 metastable atomic levels of 179Hf and the nuclear quadrupole moments of 177Hf and 179Hf

From hyperfine structure measurements in the ground multiplet 3F of 179Hf performed with the atomic beam magnetic resonance method effective radial parameters have been determined and new spectroscopic values of the nuclear quadrupole moments of 177Hf and 179Hf are evaluated.

ABMR-Ramsey patterns of strongly field dependent transitions of lithium at high magnetic fields

Using the atomic beam magnetic resonance method we observed Ramsey patterns of strongly field dependent transitions of Li, Na and Rb at high magnetic fields. The structures were of high symmetry, with half widths of the central minimums between 20 kHz and 6 kHz. In a first experiment we determined thegJ-factor ratiogJ(6Li)/gJ(7Li)=1+3(70)·10−10.

Hyperfine structure and nuclear moments of99Ru and101Ru

The atomic-beam magnetic-resonance method in combination with the triple resonance technique has been used to determine the nuclear magnetic dipole moments of99Ru and101Ru. The moments are deduced fromrf transition measurements in the5F5 and5F4 states at magnetic fields between 770 and 2400 Oe. In order to reduce the part of the uncertainty of the moments which arises from the uncertainty of the hyperfine structure constants more precise values of the constants than those available up to now were determined from low field measurements. After making corrections for hyperfine and Zeeman interactions with neighbouring atomic states we obtain the following values for the magnetic dipole moments:μ 99=−0.6381 (51)μ N andμ 101=−0.7152 (60)μ N (uncorrected for diamagnetic shielding). The results of the present work combined with the results of an earlier hyperfine structure investigation in the5F multiplet are analysed with respect to the effective-operator formalism. From this analysis we obtain the following values for the electric quadrupole moments:Q 99=0.076 (7) b andQ 101=0.44 (4) b (uncorrected for Sternheimer shielding or antishielding).

Electronic g factors eleven atomic states of Zr

The g j for eleven low-lying levels of Zr I have been measured with the atomic-beam magnetic resonance method. The agreement between the experimental g J values and theoretical predictions deduced from intermediate coupling wave functions is better than 0.1%.

Nuclear spins of 186, 187, 188, 189, 189m Au

The nuclear spins of some neutron deficient gold isotopes have been measured using the atomic-beam magnetic resonance method. The following results have been obtained: 186Au 10.7 min) I = 3, 187 Au (8.5 min) I = 1 2 , 188 Au (8.8 min) I = 1 2 , 189 Au (28.3 min) I = 1 2 and 189 m Au (4.6 min) I = 11 2 . The spins of these typical transitional nuclei are discussed briefly in terms of various nuclear models.

Hyperfine structure measurements in the4 I 9/2 ground state of141Pr

Using the atomic beam magnetic resonance method, the five hyperfine structure separations in the 4f3 6s24I9/2 ground state of 59 141 Pr have been measured. The results are:F F′ E FF′ * /h (MHz) 7 6 6477.913423(17) 6 5 5556.359848 (6) 5 4 4633.023306 (2) 4 3 3708.201146 (5) 3 2 2782.190601(15)

Precision measurement of theg J factors of metastable atomic states of88Sr and138Ba using the atomic beam magnetic resonance method

Theg J factors of the metastable states3 P 2 of88Sr and3 D 1,3 D 2,3 D 3, and1 D 2 of138Ba have been measured using the atomic-beam magnetic resonance method. The metastable states were populated by an electric discharge within the atomic-beam source. From the measurements of rf transitions between the Zeeman levels (m J =+1)↔(m J =−1) we obtained:88Sr:g J (3 P 2) =1.501124(10)138Ba:g J (3 D 3)=1.3340823 (10)g J (3 D′2)=1.1637406(11)g J (3 D 1)=0.4985751(13)g J (1 D′2)=1.003 1449(10). The relativistic and diamagnetic corrections for theg J factor of the3 P 2 state of Sr have been calculated. With these and the Schwinger correction included we getg J (3 P 2)=1.501119(12).

Nuclear spin measurements of neutron-deficient isotopes of the refractory elements

Nuclear ground and isomeric state spins of several isotopes of the refractory elements (Y, Nb, Mo, Tc, Rh, Ta, Re, Os, Ir, Pt) measured by the atomic beam magnetic resonance method, are reported. The atomic ground-state g-factor for the Os atom has also been measured.

Hyperfine structure and nuclear magnetic moments of some neutron-deficient thallium isotopes

Using the atomic-beam magnetic resonance method, hyperfine structure (h.f.s.) measurements have been performed in the2P1/2 electronic ground state of the neutron-deficient thallium isotopes193–202Tl. In the doubly odd isotopes, the magnetic dipole hyperfine interaction constantsa were determined, while in the odd-A isotopes, direct measurements of the nuclearg-factors,g I , were made. The electronicg-factor was measured in198Tl. The magnetic dipole moments of the doubly odd isotopes have been evaluated by a direct comparison with known values in the stable isotope203Tl. The moments of the odd-A isotopes are in agreement with pervious measurements by optical spectroscopy. A discussion of the magnetic dipole moments in terms of different nuclear models is included. The moments of the 2− nuclear ground states of the doubly odd isotopes may be interpreted as arising from a combination of the configurations 2− (πs1/2 vf5/2) and 2− (πs1/2 vp3/2).

Off-diagonal hyperfine structure investigations in 45Sc with the atomic beam magnetic resonance method

The off-diagonal magnetic dipole hyperfine structure constant has been measured in the atomic ground state 3d4s 2 2 D 3 2 of 45Sc with the atomic beam magnetic resonance method.

Nuclear Spins of 165Lu, 168mLu and 172Lu

The nuclear spins of some neutron-deficient lutetium isotopes have been measured using the atomic-beam magnetic resonance method. The following results have been obtained: 165Lu (12 min) I = 1/2, 168mLu (6.7 min) I = 3 and 172Lu (6.7 d) I = 4. The spin values are discussed within the framework of the Nilsson model.

Hyperfine structure investigations in DyI with the atomic beam magnetic resonance method

The hyperfine structure of the ground state configuration 4f 106s 2 of DyI was studied and the nuclear ground state magnetic dipole moments of 161Dy and 163Dy have been measured with the atomic beam magnetic resonance method.

Precision measurements of the nuclear magnetic dipole moments of6Li,7Li,23Na,39K and41K

Using the atomic beam magnetic resonance method and using the technique of separated oscillatory fields in combination with the triple resonance method the ratiosgI/gJ of the stable alkali isotopes Li, Na and K in the2S1/2-ground state have been measured at magnetic fields of about 3 kOe. Frequency shifts analogous to the Bloch-Siegert-shift, expected from theory, were observed and eliminated by extrapolation to vanishing rf-field strength. The results, uncorrected for atomic diamagnetism, are:6Li:gI/gJ=−0.22356978(10)·10−37Li:gI/gJ=−0.59042719(10)·10−323Na:gI/gJ=−0.40184406(40)·10−339K:gI/gJ=−0.07088613 (6)·10−341K:gI/gJ=−0.03890837 (4)·10−3 Furthermore, the hyperfine structure splitting constants in the2S1/2-ground states have been determined. Using the most precise absolutegJ-values available so far one can calculate absolute values for the uncorrectedgI- factors. The results are:Δν/MHz −gI·1036Li: 228.2052590(30) 0.4476540 (3)7Li: 803.5040866(10) 1.1822130 (6)23Na: 1771.6261288(10) 0.8046108 (8)39K: 461.7197202(14) 0.14193489(12)41K: 254.0138720(20) 0.07790600 (8) By comparing the absolutegI- factors with measurements received by the NMR-method, the chemical shifts of the NMR-frequencies caused by the hydrate surrounding of the alkali ions in the NMR-probe are determined.

Hyperfine structure measurements in the ground states5 F 5,5 F 4,5 F 3 and5F2 of99Ru and101Ru with the atomic beam magnetic resonance method

The hyperfine structure of the four lowest levels5F5, 4, 3, 2 of the5F ground state multiplet arising from the configuration 4d7 5s in99Ru and101Ru has been studied by the atomic — beam magnetic — resonance technique. After applying corrections due to the effects of off-diagonal hyperfine mixing we obtain the following multipole interaction constants:99Ru:A(5F5)=−204.5514(33) MHzB(5F5)=27.281 (62) MHzA5F4=−163.6845(36) MHzB(5F4)=17.455(52) MHzA5F3=−135.0294(37) MHzB(5F3)=10.164(50) MHzA(5F2)=− 82.5325(27) MHzB(5F2)=5.457(22) MHz101Ru:A(5F5)=−229.2881(33) MHzB(5F5)=158.934(62) MHzA(5F4)=−183.4744(36) MHzB(5F4)=101.799(52) MHzA(5F3)=−151.3502(38) MHzB(5F3)=59.323(50) MHzA(5F2)=−92.4974(27) MHzB(5F2)=31.869(23) MHz. The magnetic dipole and the electric quadrupole moments of the99Ru and101Ru nuclear ground states as calculated from these constants are the following:μ I (99Ru)=−0.594(119) nmQ(99Ru)=0.077 (15) barnsμ I (101Ru)=−0.666(133)nmQ(101Ru)=0.45 (9) barns. From measurements of the Zeeman effect in the even isotope102Ru we find the followingg J -factors for the5F ground multiplet:g J (5F5)=1.397741(20)g J (5F4)=1.347604(20)g J (5F3)=1.248988(20)g J (5F2)=1.001120(3).

Atomic-beam investigations of some antimony nucleides

The nuclear spins of some antimony isotopes and the hyperfine structure constants of 117Sb have been measured by the atomic-beam magnetic resonance method. The results are 116Sb (16min) I = 3, 116 m Sb (60.4 min)I = 8, 118 m Sb (5.0 h) I = 8, 120 m Sb (5.76 d) I = 8, 128 Sb (9.0 h) I = 8 and 117 Sb (2.8 h) a = −305(5) MHz, b = 3(21) MHz . The corresponding nuclear moments of 117 Sb, μ I = 3.43(6) n.m. and Q = 0.2(1.2) b, have been evaluated through a direct comparison with known values in the stable nucleus 121Sb. The magnetic dipole moment which deviates from an earlier measurement, is in good agreement with theoretical predictions.

Hexadecapole interaction in the atomic ground state of165Ho

Using the atomic beam magnetic resonance method several hyperfine transitions in the ground state of165Ho were measured at magnetic fields near zero Oe. Including a hexadecapole interaction constantD a perfect fit of the seven hyperfine separations was possible giving the following results:A′=800.583645 (6)MHz,C′=−1.504 (37)kHzB′=−1668.00527 (33)MHz,D′=−0.137 (14)kHz. These interaction constants have been corrected for second order hyperfine interaction within the4I ground multiplet. The corrected constants are the following:A=800.583173 (36)MHz,C=−0.249 (140)kHzB=−1668.078 70 (330) MHz,D=−0.148 (16) kHz. Using a value for 〈r4f/−5〉Ho of Fraga a nuclear hexadecapole moment can be calculated:Π(165Ho)=0.89·10−48cm4. Because of severe uncertainties still present in the theory for calculating the electronic matrix elements this value can be only regarded as highly speculative.

Nuclear Spins of Some Neutron-deficient Tin Isotopes

The nuclear spins of some neutron-deficient tin isotopes have been measured by the atomic-beam magnetic resonance method. The results are: 109Sn (18.0 min) I = 7/2, 110Sn (4.0 h) I = 0, 111Sn (35.3 min) I = 7/2 and 113mSn (21.4 min) I = 7/2. The spin values are compared with predictions from spectroscopic and theoretical studies.

Hyperfine structure in the metastableDstates of atomic barium

The atomic-beam magnetic-resonance method has been used to measure the magnetic dipole and electric quadrupole hyperfine-structure interaction constants $A$ and $B$ for the $^{3}D_{3}$, $^{3}D_{2}$, and $^{1}D_{2}$ states of the... $(6s)(5d)$ configuration for $^{135}\mathrm{Ba}$ and $^{137}\mathrm{Ba}$. The experimental results for $^{135}\mathrm{Ba}$ are $A(^{1}D_{2})=\ensuremath{-}73.429(4)$ MHz, $B(^{1}D_{2})=+38.710(15)$ MHz, $A(^{3}D_{2})=+370.6(7)$ MHz, $B(^{3}D_{2})=+18.3(22)$ MHz, $A(^{3}D_{3})=+408.1(14)$ MHz, $B(^{3}D_{3})=+20(8)$ MHz; and for $^{137}\mathrm{Ba}$, $A(^{1}D_{2})=\ensuremath{-}82.180(3)$ MHz, $B(^{1}D_{2})=+59.564(14)$ MHz, $A(^{3}D_{2})=+413.9(9)$ MHz, $B(^{3}D_{2})=+26.8(30)$ MHz, $A(^{3}D_{3})=+455.4(16)$ MHz, $B(^{3}D_{3})=+36(9)$ MHz. A comparison is made between the value of the electric quadrupole moment of the $^{137}\mathrm{Ba}$ nucleus obtained from these results, which depend on the interaction of the $5d$ electron, and the value obtained from earlier results, which depend on the interaction of the $6p$ electron. There is a substantial difference in the values of Q($^{137}\mathrm{Ba}$) obtained from these two sets of measurements if one does not take the quadrupole shielding into account. Taking the quadrupole shielding into account markedly reduces this difference.