Two-quasiparticle excitations and collectivity in the weakly-deformed transitional isotopes 104, 106, 108Cd

Using the generalized centroid-shift method on the Rutgers tandem, the following half-lives of ¹⁰⁶Cd excited states were measured in the reaction ⁹³Nb(¹⁶O, p2n): $\text{T}{}_{\mathrm{<mtext>1</mtext><mtext>2</mtext>}}\text{(3679.0}\text{keV}\text{) = 0.7}{}^{\mathrm{+0.1}}{}_{\mathrm{?0.3}}\text{ns}\text{, T}{}_{\mathrm{<mtext>1</mtext><mtext>2</mtext>}}\text{(3507.8}\text{keV}\text{) = 1.2 ± 0.4}\text{ns}\text{, T}{}_{\mathrm{<mtext>1</mtext><mtext>2</mtext>}}\text{(3044.2}\text{keV}\text{) = 0.4 ± 0.1}\text{ns, and}\text{T}{}_{\mathrm{<mtext>1</mtext><mtext>2</mtext>}}\text{(2330.7}\text{keV}\text{) = 0.6 ± 0.2}\text{ns}$. With the same method applied on the Rossendorf cyclotron, the following half-lives were measured in the reactions ${}^{\mathrm{102,\; 106}}\text{Pd}\text{(α, 2}\text{n}\text{): T}{}_{\mathrm{<mtext>1</mtext><mtext>2</mtext>}}\text{(2902.0}\text{keV}\text{) = 0.8}{}^{\mathrm{+0.2}}{}_{\mathrm{?0.1}}\text{ns}\text{(}{}^{104}\text{Cd}\text{)}$ as well as $\text{T}{}_{\mathrm{<mtext>1</mtext><mtext>2</mtext>}}\text{(3737.3}\text{keV}\text{) = 0.2 ± 0.1}\text{ns}$, $\text{T}{}_{\mathrm{<mtext>1</mtext><mtext>2</mtext>}}\text{(3223.7}\text{keV}\text{) = 0.2 ± 0.1}\text{ns}$, $\text{T}{}_{\mathrm{<mtext>1</mtext><mtext>2</mtext>}}\text{(3057.4}\text{keV}\text{) = 0.10 ± 0.05}\text{ns}$, $\text{T}{}_{\mathrm{<mtext>1</mtext><mtext>2</mtext>}}\text{(2975.3}\text{keV}\text{) = 0.15 ± 0.10}\text{ns}$, $\text{T}{}_{\mathrm{<mtext>1</mtext><mtext>2</mtext>}}\text{(3110.5}\text{keV}\text{) = 0.3 ± 0.1}\text{ns}$, and $\text{T}{}_{\mathrm{<mtext>1</mtext><mtext>2</mtext>}}\text{(2565.2}\text{keV}\text{) = 0.2 ± 0.1}\text{ns}\text{(}{}^{108}\text{Cd}\text{)}$. The results reveal the non-collective (two-quasiparticle) character of several states above 2.9 MeV in ^{104, 106, 108}Cd, in qualitative accordance with predictions of the slightly-deformed-rotor model. They concern completely aligned [h_{$\text{11}\text{2}$}g_{$\text{7}\text{2}$}] (9^??11^?-13^?, etc.) as well as semi-decoupled [h_{$\text{11}\text{2}$}d_{$\text{5}\text{2}$}] (6^?-8^?-10^?, etc.) two-quasineutron band structures. Further, the possible character of 8⁺ (two-quasiproton) excitations, 5⁺ (two-quasineutron) states and of other intrinsic excitations is discussed. The experimental findings present a challenge to current theories of transitional nuclei for a quantitative treatment of absolute γ-ray transition strengths.     

Absolute E1, ΔK = 1 transition probabilities between multi-quasiparticle high-spin states in 176Hf and 178Hf

Applying the generalized centroid shift method in (α, 2n) reactions, the half-lives of the 3080 keV 15⁺ state in ¹⁷⁶Hf and of the 1637 keV 5^? state in ¹⁷⁸Hf have been measured as $\text{T}{}_{\mathrm{<mtext>1</mtext><mtext>2</mtext>}}\text{= 0.20}{}^{\mathrm{+0.12}}{}_{\mathrm{?0.08}}\text{ns}$ and $\text{T}{}_{\mathrm{<mtext>1</mtext><mtext>2</mtext>}}\text{= 0.40 ± 0.10}\text{ns}$, respectively. B(El) values of K-allowed E1 transitions $\text{n}\text{9}\text{2}{}^{\mathrm{+}}\text{[624]→}\text{7}\text{2}{}^{\mathrm{?}}\text{[514]}$ are derived, and together with other data on similar transitions in odd-A nuclei, compared with predictions of the Nilsson plus pairing model. In ¹⁷⁶Hf, the 15⁺ and 14^? states at 3080 and 2866 keV, respectively, appear as quite pure deformed 4QP configurations. In the 2QP state at 1637 keV in ¹⁷⁸Hf, possible strong mixing of vibrational components is discussed coupled via 2QP K-admixtures arising from the partial alignment of the $\text{i}{}_{\mathrm{<mtext>13</mtext><mtext>2</mtext>}}$ neutron.     

Transition probabilities in the doubly odd nuclei 176Lu and 182Ta

The depopulation of isomeric states in ¹⁷⁶Lu and ¹⁸²Ta was studied in the (n, γ) reaction by means of delayed γ-γ coincidence measurements with NaI(Tl) and Ge(Li) detectors. The following half-lives, unknown so far, have been obtained for ¹⁷⁶Lu: $\text{T}{}_{\mathrm{<mtext>1</mtext><mtext>2</mtext>}}\text{(198.0}\text{keV}\text{) = 35.0 ± 1.0}\text{ns}$, $\text{T}{}_{\mathrm{<mtext>1</mtext><mtext>2</mtext>}}\text{(638.8}\text{keV}\text{) = 8.0±1.0}\text{ns}$ and $\text{T}{}_{\mathrm{<mtext>1</mtext><mtext>2</mtext>}}\text{(662.1}\text{keV}\text{) = 6.3±0.5}\text{ns}$; and for ¹⁸²Ta: $\text{T}{}_{\mathrm{<mtext>1</mtext><mtext>2</mtext>}}\text{(270.4}\text{keV}\text{) = 1.2 ± 0.2}\text{ns}$, $\text{T}{}_{\mathrm{<mtext>1</mtext><mtext>2</mtext>}}\text{(402.6}\text{keV}\text{) = 1.00 ± 0.05}\text{ns}$ and $\text{T}{}_{\mathrm{<mtext>1</mtext><mtext>2</mtext>}}\text{(443.6}\text{keV}\text{) = 2.2 ± 0.2}\text{ns}$. The existence of the isomeric level at 443.6 keV in ¹⁸²Ta was confirmed. Weisskopf hindrance factors have been deduced for the K- and Ω-forbidden transitions. The K-allowed transitions are considered in terms of the Nilsson model taking into account pairing correlations. The experimental results for the transitions de-exciting the 270.4 keV level in ¹⁸²Ta agree with earlier model predictions including band mixing effects. The influence of the pairing effect on K-allowed E1 transitions in doubly odd nuclei is demonstrated.     

Magnetic moments of Jπ = 192− mirror states in 43Ti and 43Sc

The time-differential perturbed angular distribution method was used to determine the g-factors of the $\text{(}\text{f}{}_{\mathrm{<mtext>7</mtext><mtext>2</mtext>}}\text{)}{}^3\text{19}\text{2}{}^{\mathrm{?}}$ states in ⁴³Ti and ⁴³Sc. The results for the mass 43 mirror pair are: ${}^{43}\text{Ti}\text{: g = 0.760 ± 0.001, T}{}_{\mathrm{<mtext>1</mtext><mtext>2</mtext>}}\text{, = 560 ± 6}\text{ns}$, ${}^{43}\text{Sc}\text{: g = 0.3286± 0.0007, T}{}_{\mathrm{<mtext>1</mtext><mtext>2</mtext>}}\text{= 473 ± 5}\text{ns}$. Considering in addition the magnetic moments in A = 41 and 42, it is suggested that the deformed states considered by Johnstone and Castel and by Erikson are responsible for the observed large deviations from the Schmidt values.     

Isomeric yrast states in 206Tl

We have found isometric states in ²⁰⁶Tl with $\text{J}{}^{\mathrm{\pi }}\text{= 12}{}^{\mathrm{?}}\text{(T}{}_{\mathrm{<mtext>1</mtext><mtext>2</mtext>}}\text{= 3.76}\text{min}\text{)}$, 7⁺ (10ns) and 5⁺ (78ns) and have identified their proton-neutron hole structure. New electromagnetic properties of proton hole orbitals have been determined.     

Study of the three-proton three-neutron-hole nucleus 208At

Levels in ²⁰⁸At were populated in the ²⁰⁹Bi(α, 5n) reaction, and the subsequent radiation was studied using γ-spectroscopic methods including γ-ray excitation function and angular distribution, γγ(t) coincidence and γt measurements, as well as measurements of conversion electrons. The excited spectrum of ²⁰⁸At is found to consist of two almost disconnected parts which are proposed to originate from seniority-three proton and neutron cascades. Two isometric states are observed. A $\text{T}{}_{\mathrm{<mtext>1</mtext><mtext>2</mtext>}}\text{= 45 ± 2}\text{ns}$ state at 1090 keV is proposed to have the main configuration and J^π = 10^?. A high-spin isomer with $\text{T}{}_{\mathrm{<mtext>1</mtext><mtext>2</mtext>}}\text{= 1.5 ± 0.2 μs at 2276}\text{keV}$ is assigned to be the state. Shell-model arguments are used to assign configurations to most of the observed levels. Transition rates are discussed.     

Lifetimes of the Si I 3p4s 1P1 and 3p3d 1P1 states

A beam of metastable silicon atoms was produced by collisional dissociation of silicon molecules and selectively excited by a pulsed dye laser. The lifetimes of the excited Si I states were directly determined from the fluorescence decay curve: $\text{τ(3p4s}{}^1\text{P}{}_1\text{) = 4.1 (4) ns}$, $\text{τ(3p4s}{}^3\text{P}{}_2\text{) = 4.4 (4) ns}$, $\text{τ(3p3d}{}^1\text{P}{}_1\text{) = 8.1(5) ns}$.     

Beta decay studies in the vicinity of 13250Sn82: Excited states in 13051Sb, 13052Te and 13252Te

Using the OSIRIS on-line isotope separator facility, the decays of ¹³⁰Sn and ^{130, 132}Sb have been studied. On the basis of singles γ and γ-γ coincidence Ge(Li) spectra and conversion electron Si(Li) measurements, level schemes for ¹³⁰Sb, ¹³⁰Te and ¹³²Te have been constructed. The corresponding half-lives have been measured using multiscaling technique. The 3.8 min ground state of ¹³⁰Sn populates only positive parity states in the πν^?3 nucleus ¹³⁰Sb: the energetically lowest 5⁺ state with the $\text{(π1}\text{g}{}_{\mathrm{<mtext>7</mtext><mtext>2</mtext>}}\text{, ν2}\text{d}{}_{\mathrm{<mtext>3</mtext><mtext>2</mtext>}}\text{)}$ configuration assignment; the $\text{T}{}_{\mathrm{<mtext>1</mtext><mtext>2</mtext>}}\text{= 3.6 ± 0.3}\text{ns}\text{4}{}^{\mathrm{+}}$ state at 70.0 keV; the 2⁺ state at 262.5 keV; the (0, 1)⁺ state at 697.2 keV; the 3⁺ state at 813.1 keV and the 1⁺ state at 1042.3 keV excitation energy. A 1.7 min isomeric state in ¹³⁰Sn, with the tentative spin assignment (7^?), populates several odd parity levels in ¹³⁰Sb. These arise from the $\text{(π1}\text{g}{}_{\mathrm{<mtext>7</mtext><mtext>2</mtext>}}\text{, ν1}\text{h}{}_{\mathrm{<mtext>11</mtext><mtext>2</mtext>}}{}^{-1}\text{)}$ and/or $\text{(π2}\text{d}{}_{\mathrm{<mtext>5</mtext><mtext>2</mtext>}}\text{, ν1}\text{h}{}_{\mathrm{<mtext>11</mtext><mtext>2</mtext>}}{}^{-1}\text{)}$ configurations and are located 84.7 keV (6^?), 144.9 keV (7^?), 688.5 keV and 1044.0 keV above the 40 min 8^? β- decaying state. No transitions between odd and even parity states have been observed.The most important excited states in ¹³⁰Te found in the β^? decay of the 6.6 min ¹³⁰Sb 5⁺ state are: 839.4 keV, 2⁺; 1632.8 keV, 4⁺; 1815.1 keV, 6⁺; 2100.8 keV, 5^?.Levels in the π²ν^?2 nucleus ¹³²Te were observed in the β^? decays of the 2.8 min ¹³²Sb (4⁺) and the 4.2 min ¹³²Sb (8^?) states. Unique spin and parity assignments have been given to the following states: 973.9 keV, 2⁺; 1670.7 keV, 4⁺; 1774.1 keV, 6⁺; 1924.7 keV, 7^?; 2053.0 keV, 5^?.     

Decay of the ground state and the 292+ isomer in 217Ac and g-factor measurements from perturbed α-particle angular distributions

The nucleus ²¹⁷Ac was studied using the ²⁰⁵Tl(¹⁶O, 4n), ²⁰⁶Pb(¹⁵N, 4n) and ²⁰⁹Bi(¹²C, 4n) reactions. The mesurements included αγ, γγ, α-ce and ce-ce coincidence experiments as well as γ-ray and α-particle perturbed angular distribution studies. Results are $\text{g(}{}^{\mathrm{217g}}\text{Ac}\text{) = + 0.85(1)}$ and $\text{T}{}_{\mathrm{<mtext>1</mtext><mtext>2</mtext>}}\text{(}{}^{\mathrm{<mtext>217</mtext><mtext>g</mtext>}}\text{Ac}\text{) = 69(4)}\text{ns}$, the shortest known α-decay of a ground state. ^217mAc decays mainly by a γ-cascade, but also by α-emission to the single-particle states $\text{π}\text{h}{}_{\mathrm{<mtext>9</mtext><mtext>2</mtext>}}\text{,}\text{f}{}_{\mathrm{<mtext>7</mtext><mtext>2</mtext>}}\text{,}\text{i}{}_{\mathrm{<mtext>f</mtext><mtext>13</mtext><mtext>2</mtext>}}$ of ²¹³Fr. Spins and parities of levels to the $\text{29}\text{2}$⁺ isomer at 2013 keV with $\text{T}{}_{\mathrm{<mtext>1</mtext><mtext>2</mtext>}}\text{= 740(40)}\text{ns}$ and g = + 0.347(5) are determined. The level scheme of ²¹⁷Ac and the α-decay of N = 128 isotones are discussed.     

Infrared bands of 12C2HD

The rotational structure of about 40 bands of ¹²C₂HD observed in the region 6000?600 cm^?1 has been measured and interpreted with the purpose of determining a comprehensive set of molecular constants for this isotopic variety of acetylene. Combining these data with the results for ¹²C₂H₂ and ¹²C₂D₂, a reevaluation of the equilibrium internuclear distances for the acetylene molecule has been made: $\text{r}{}_{\mathrm{e}}\text{(CH) = 1.06215 ± 17 × 10}{}^{\mathrm{?5}}\text{A}\text{?}$ and $\text{r}{}_{\mathrm{e}}\text{(CC) = 1.20257 ± 9 × 10}{}^{\mathrm{?5}}\text{A}\text{?}$ were obtained. This paper presents all the molecular constants derived in this study.     

Magnetic moment and half-life of the isomeric 112− state in 107Cd

An isomeric level in ¹⁰⁷Cd at 845 keV populated by the reactions ¹⁰⁷Ag(p, n), ¹⁰⁶Cd(d, p) and ¹⁰⁴Pd(α, n) has been observed. The half-life of this state is $\text{T}{}_{\mathrm{<mtext>1</mtext><mtext>2</mtext>}}\text{= 77(7)}\text{ns}$, and the spin and parity are $\text{I}{}^{\mathrm{\pi }}\text{=}\text{11}\text{2}{}^{\mathrm{?}}$. The magnetic moment has been determined by the pulsed beam time-differential perturbed angular distribution method (DPAD) to be μ = ?1.012(12) n.m.     

Rotational bands in 195, 197Tl

High-spin states in ^{195, 197}Tl have been populated with (α, xn) reactions and studied by means of in-beam γ-ray and e^? spectroscopic methods. Complementary studies of the decay of ^{195, 197}Pb to ^{195, 197}Tl have been carried out. Several new features have been observed in these nuclei. The $\text{9}\text{2}{}^{\mathrm{?}}$ bands of ^{195, 197}T1. extended to $\text{27}\text{2}{}^{\mathrm{(?)}}$ and $\text{29}\text{2}{}^{\mathrm{(?)}}$, respectively, show a quenching of energy spacings between the $\text{23}\text{2}{}^{\mathrm{?}}$, $\text{25}\text{2}{}^{\mathrm{?}}$, $\text{27}\text{2}{}^{\mathrm{(?}}$ and $\text{29}\text{2}{}^{\mathrm{(?}}$ states. This has been interpreted as resulting from the coupling of a $\text{h}{}_{\mathrm{<mtext>9</mtext><mtext>2</mtext>}}$ proton to the ($\text{π}\text{h}{}^{\mathrm{?2}}{}_{\mathrm{<mtext>11</mtext><mtext>2</mtext>}}\text{)}{}_{\mathrm{8+,\; 10+}}$ configurations in the core nuclei ^{194, 196}Hg. Furthermore, positive-parity bands based on $\text{15}\text{2}{}^{\mathrm{+}}$ states were established up to the $\text{35}\text{2}{}^{\mathrm{(+)}}$ and $\text{29}\text{2}{}^{\mathrm{(+)}}$ states in ^{195, 197}Tl respectively. Probably these bands originate from the coupling of a h${}_{\mathrm{<mtext>9</mtext><mtext>2</mtext>}}$ proton to a broken neutron pair. This pair consists of a rotation-aligned $\text{i}{}_{\mathrm{<mtext>13</mtext><mtext>2</mtext>}}$ neutron and a low-j neutron in the $\text{P}{}_{\mathrm{<mtext>1</mtext><mtext>2</mtext>}}$, $\text{P}{}_{\mathrm{<mtext>3</mtext><mtext>2</mtext>}}$ or $\text{f}{}_{\mathrm{<mtext>5</mtext><mtext>2</mtext>}}$ shell. It is known to constitute the 5^? bands in ^{194, 196}Hg.     

Study of the 91Zr(d, 3He)90Y reaction

The ⁹¹Zr(d, ³He) reaction was studied at a deuteron energy of 28 MeV. Angular distributions were measured from 13° to 47°; l_p values were extracted for the prominent lines of ⁹⁰Y. The l_p values and transition strengths were determined by DWBA analysis. The angular distributions for the $\text{(π}\text{p}{}_{\mathrm{<mtext>1</mtext><mtext>2</mtext>}}\text{)(ν}\text{d}{}_{\mathrm{<mtext>5</mtext><mtext>2</mtext>}}\text{)}$ doublet (g.s. and 0.20 MeV state) exhibit the characteristic l = 1 shape. States at 1.42, 1.57, 1.64 and 1.81 MeV were also populated strongly in the (d, ³He) reaction; the 1.42, 1.57 and 1.81 MeV levels contain l= 1 transition strength and are most likely members of the $\text{(π}\text{p}{}_{\mathrm{<mtext>3</mtext><mtext>2</mtext>}}{}^{\mathrm{?1}}\text{)(ν}\text{d}{}_{\mathrm{<mtext>5</mtext><mtext>2</mtext>}}\text{)}$ multiplet. The 2.03 MeV state has a characteristic l = 3 angular distribution and is suggested to be the only member of the $\text{(π}\text{f}{}_{\mathrm{<mtext>3</mtext><mtext>2</mtext>}}{}^{\mathrm{?1}}\text{)(ν}\text{d}{}_{\mathrm{<mtext>5</mtext><mtext>2</mtext>}}\text{)}$ sextet to be unambiguously observed in this study, most probably the 5^? or 4^? member. The members of the $\text{(π}\text{g}{}_{\mathrm{<mtext>5</mtext><mtext>2</mtext>}}\text{)(ν}\text{d}{}_{\mathrm{<mtext>9</mtext><mtext>2</mtext>}}\text{)}$ sextet were populated weakly (less than 100 μb/sr) in this reaction.     

Recoil-distance lifetime measurements in 51Cr, 53Cr, 53Mn and 53Fe

Levels in ⁵¹Cr, ⁵³Cr, ⁵³Mn and ⁵³Fe were excited via (α, n) or (α, p) reactions. Using the recoil-distance method, mean-lives (in ps) have been obtained for excited states (keV) in the residual nuclei: ${}^{51}\text{Cr}\text{(2256) = 66±2,}{}^{53}\text{Cr}\text{(1536) = 21.5±3.5,}{}^{53}\text{Cr}\text{(2173) = 6.7±3.1,}{}^{53}\text{Mn}\text{(2564) = 20}{}^{\mathrm{+8}}{}_{\mathrm{?6}}\text{and}{}^{53}\text{Fe}\text{(1424) = 4.0±1.0}$. Reduced transition probabilities calculated from these values are compared with the available theoretical values.     

The quadrupole moments of the 5− states in 116Sn, 118Sn and 120Sn

The quadrupole interaction frequencies $\text{ω}{}_0\text{=}\text{3eQ}{}_1\text{V}{}_{\mathrm{zz}}\text{41(21-1)}\text{h}\text{?}$ in the 5^? state of ¹¹⁸Sn have been measured by time differential perturbed angular correlation technique in Sn, Sb and (95% Sn+5% Sb) environments. The ω₀ for ¹¹⁶Sn was determined in Sn environment only. With the help of the known electric field gradient ¹) of Sn in a Sn lattice the quadrupole moments have been deduced as $\text{Q(5}{}^{\mathrm{?}}\text{,}{}^{118}\text{Sn}\text{) = ±0.10(4) b}\text{and}\text{Q(5}{}^{\mathrm{?}}\text{,}{}^{116}\text{Sn}\text{) = ±0.165(60)}\text{b}$. These values together with the known²) quadrupole moment of the analogous 5^? state in ¹²⁰Sn are interpreted in terms of the pure single-particle model. The data exhibit the expected strong systematic variation of Q_I with the number of particles in the h_{$\text{11}\text{2}$}. subshell which is being filled with 1, 3 and 5 neutrons in ¹¹⁶Sn, ¹¹⁸Sn, and ¹²⁰Sn, respectively.     

Observation of rotation-aligned bands in the odd-odd nuclei 190, 192, 194Au

Two rotation-aligned bands based on an (11)^? isomer and a (12)^? state, respectively, were observed in ^{190, 192, 194}Au. They have most probably $\text{(πh}{}_{\mathrm{<mtext>11</mtext><mtext>2</mtext>}}{}^{\mathrm{?1}}\text{μi}{}_{\mathrm{<mtext>13</mtext><mtext>2</mtext>}}{}^{\mathrm{?1}}\text{)}$ configurations in agreement with recent theoretical predictions in the framework of the triaxial-rotor-plus-particle model.     

Neutron-proton shell model multiplets in 88Y and 90Y from a study of the (α, nγ) reaction

The non-selective nature of the (α, nγ) reaction has been used to complement information from charged-particle reactions on the level structure of ⁸⁸Y and ⁹⁰Y. The γ-ray spectra were recorded with a 25 cm³ Ge(Li) detector at 90° to the beam using primarily targets of ⁸⁵Rb₂CO₃ and ⁸⁷Rb₂CO₃ and α-particle energies of 11.8, 12.2 and 13.0 MeV. The resulting transitions were accommodated in level schemes that involved primarily the following shell model configurations: $\text{(π}\text{p}{}_{\mathrm{<mtext>1</mtext><mtext>2</mtext>}}\text{)}{}^1\text{(ν}\text{g}{}_{\mathrm{<mtext>9</mtext><mtext>2</mtext>}}\text{)}{}^{\mathrm{?1}}$, $\text{(π}\text{g}{}_{\mathrm{<mtext>9</mtext><mtext>2</mtext>}}\text{)}{}^{\mathrm{?1}}\text{(ν}\text{g}{}_{\mathrm{<mtext>9</mtext><mtext>2</mtext>}}\text{)}{}^1$, $\text{(π}\text{p}{}_{\mathrm{<mtext>1</mtext><mtext>2</mtext>}}\text{)}{}^1\text{(ν}\text{p}{}_{\mathrm{<mtext>1</mtext><mtext>2</mtext>}}\text{)}{}^{\mathrm{?1}}$, $\text{(π}\text{f}{}_{\mathrm{<mtext>5</mtext><mtext>2</mtext>}}\text{)}{}^{\mathrm{?1}}\text{(ν}\text{g}{}_{\mathrm{<mtext>9</mtext><mtext>2</mtext>}}\text{)}{}^{\mathrm{?1}}$ in ⁸⁸Y and $\text{(π}\text{p}{}_{\mathrm{<mtext>1</mtext><mtext>2</mtext>}}\text{)}{}^1\text{(ν}\text{d}{}_{\mathrm{<mtext>5</mtext><mtext>2</mtext>}}\text{)}{}^1$, $\text{π}\text{g}\text{(}{}_{\mathrm{<mtext>9</mtext><mtext>2</mtext>}}\text{)}{}^1\text{(ν}\text{d}{}_{\mathrm{<mtext>5</mtext><mtext>2</mtext>}}\text{)}{}^1$,$\text{(π}\text{p}{}_{\mathrm{<mtext>1</mtext><mtext>2</mtext>}}\text{)}{}^1\text{(ν}\text{s}{}_{\mathrm{<mtext>1</mtext><mtext>2)</mtext>}}\text{)}{}^1$ in ⁹⁰Y.     

Magnetic moment of a core-excited isomeric state in 210Po

The g-factor of the core-excited isomeric 13^? state in ²¹⁰Po has been determined to be +0.546 ± 0.012 with the time-differential spin-rotation method in the ²⁰⁸Pb(α, 2n)²¹⁰Po reaction. This value supports the configuration of $\text{[(π}\text{h}{}^2{}_{\mathrm{<mtext>9</mtext><mtext>2</mtext>}}\text{)8}{}^{\mathrm{+}}\text{? 5}{}^{\mathrm{?}}\text{(}{}^{208}\text{Pb}\text{)] 13}{}^{\mathrm{?}}$.