Half-life and magnetic moment of the 1+ first excited state in116Sb

The life-time and the magnetic dipole moment of the 1⁺ isomeric state in¹¹⁶Sb have been measured by the TDPAD method. The state was populated in the reaction¹¹⁶Sn(p, n)¹¹⁶Sb atE _p =15 MeV. The obtained results,μ(1⁺,¹¹⁶Sb)=+2.47(9) n.m. andT _1/2= 194(4) ns, support the pure single particle [πd _5/2*vd _3/2] configuration for the 1⁺ isomeric state.     

Luminescence properties of K1/2Bi1/2TiO3:Pr3+ and Na1/2Bi1/2TiO3:Pr3+

The luminescence properties of K(1/2)Bi(1/2)TiO(3):Pr(3+) and Na(1/2)Bi(1/2)TiO(3):Pr(3+) powders are investigated in the temperature range 10-600 K. The experimental data are interpreted on the basis of metal-to-metal charge transfer processes and by considering Bi(3+)-to-Pr(3+) sensitization effects.     

Isomeric transitions in203Bi and205Bi

High spin states in^{203, 205}Bi, populated in the^{203, 205}Tl (α,4n) reactions, have been studied using gamma-ray and conversion-electron spectroscopy. Several previously unobserved isomeric transitions were identified by electron-electron coincidence measurements in both isotopes and in²⁰⁵Bi a new isomer was found. The observed states can be explained as arising from couplings of the oddh _9/2 proton to neutron states in the neighbouring Pb cores. Reduced transition probabilities are derived and discussed.     

Half-life of the ground state of 53Co

The half-life of ⁵³Co(g.s.) was measured by observing its positron emission following the ³⁹K.( ¹⁶O, 2n) reaction induced by a chopped ¹⁶O beam. The contributions to the half-life of positrons from competing reaction products were considered. The final spin distribution and the isomeric ratio values for ${}^{\mathrm{53m}}\text{Co}{}^{53}\text{Co(}\text{g.s.}\text{)}$ and ${}^{\mathrm{53m}}\text{Fe}{}^{53}\text{Fe(}\text{g.s.}\text{)}$ were calculated by the spindependent nuclear evaporation model and found to be different, the former much smaller than the latter. The ${}^{\mathrm{53m}}\text{Fe}{}^{53}\text{Fe(}\text{g.s.}\text{)}$ isomeric ratios were measured for ³⁹K.+ ¹⁶O as well as for ⁴⁰C + ¹⁶O reactions and were found to be in agreement with the above theoretical prediction. On the basis of the smallness of the calculated ${}^{\mathrm{53m}}\text{Co}{}^{53}\text{Co(}\text{g.s.}\text{)}$ ratio, the half-life of ⁵³Co(g.s.) was determined to be $\text{T}{}_{\mathrm{<mtext>1</mtext><mtext>2</mtext><mtext>\; =\; 262\; \pm \; 25\; </mtext><mtext>ms</mtext>}}$.     

QED and hyperfine splitting in the 2s1/2−2p3/2 X-ray transition in lithium-like Bi80+

The measurement of the Bi⁸⁰⁺ 2s_1/2−2p_3/2 transition energy is discussed. The measurement resolved the hyperfine splitting of the (1s²2s) F=4,5 ground configuration and allowed a determination of the Lamb shift contributions with a precision of about 9 × 10^-4 providing the most accurate test of QED in a high-Z ion to date. This revised version was published online in July 2006 with corrections to the Cover Date.     

Half-life,g-factor and relaxation of the nuclear orientation of the isomeric 11/2− state in139Pr

By time-differential observation of the perturbed angular distribution in an external magnetic field, the g-factor of the 11/2^? isomeric state in¹³⁹Pr has been measured, g = +1.20 ± 0.09. The angular distribution also shows an attenuation with relaxation time, τ _R = 19 ± 6 ns. This relaxation is due to paramagnetic interaction of the nucleus with the 4f-electrons. Our determination of the isomeric half-life,T _1/2= 45.5 ±0.9 ns does not agree with previous measurements.     

Subsolidus phase relation in the Bi2O3-Fe203-La2O3 system

Bismuth-containing semiconductor material is a hot topic in photocatalysts because of its effective absorption under the visible light. In this paper, we expect to explore a new bismuth-based photocatalyst by studying the subsolidus phase relations of the Bi2O3-Fe2O3-La2O3 system. The X-ray diffraction data shows that in this ternary system the ternary compound does not exist, while seven binary compounds （including one solid solution series Bi1-xLaxO1.5 with 0.167 〈 x 〈 0.339） are obtained and eight compatibility triangles are determined.     

23Na NMR in the relaxor ferroelectric Na1/2Bi1/2TiO3

The ²³Na NMR spectra of a Na_1/2Bi_1/2TiO₃ crystal are studied at frequencies of 79.4 and 15.7 MHz in the temperature range 150–720 K. It is revealed that, at all temperatures, the crystal contains regions with a nearly cubic matrix and polar clusters. The temperature dependence of the local distortion of the Na environment in the clusters is determined. The dynamics of the reorientation of the local cluster polarization in the tetragonal and trigonal NBT phases is analyzed.     

Effect of excess Bi2O3 on the electrical properties and microstructure of (Bi1/2Na1/2)TiO3 ceramics

(Bi_1/2Na_1/2)TiO₃ ceramics (BNT) with 0–6 mol% of excess Bi₂O₃ are prepared by conventional solid-state sintering. The electrical properties of the samples are examined. The addition of excess Bi₂O₃ reduces the leakage current of BNT ceramics significantly, thus facilitating the poling process, and improves their piezoelectric properties slightly for certain amounts of added Bi₂O₃. BNT ceramics have very high dielectric constants and dissipation factors at low frequency and high temperature due to their high conductivity. Adding excess Bi₂O₃ to BNT ceramics affects their dielectric behavior and phase transition temperatures. Grain growth is suppressed by adding Bi₂O₃ and no second phase is observed for BNT ceramics with up to 6 mol% of excess Bi₂O₃ added.     

Multiple Coulomb excitation of a 70Ge beam and the interpretation of the 02 + state as a deformed intruder

Electromagnetic properties of the low-lying states in a ⁷⁰Ge nucleus were studied through the multiple Coulomb excitation of a ⁷⁰Ge beam with a ^natPb target. Relative γ-ray intensities were measured as a function of emission angle relative to the scattered projectile. Sixteen E2 matrix elements, including diagonal ones, for 6 low-lying states have been determined using the least-squares search code GOSIA. The expectation values 〈Q ²〉 of 0₁ ⁺ and 0₂ ⁺ states in ⁷⁰Ge are compared with those in ^{72, 74, 76}Ge. Simple mixing calculations indicate that the 0₂ ⁺ states in ⁷⁰Ge and ⁷²Se can be treated as deformed intruder states. It is shown that the deformed intruder becomes the ground state in ⁷⁴Kr. These interpretations of the 0₂ ⁺ states in this region are compared with the potential-energy surface calculations by the Nilsson-Strutinsky model, which allow to interpret the experimental results in a qualitative way from the theoretical point of view. Received: 2 September 2002 / Accepted: 5 November 2002 / Published online: 25 February 2003 RID="a" ID="a"e-mail: sugawara@pf.it-chiba.ac.jp Communicated by D. Schwalm     

Self-energy contribution to the ground state hyperfine splitting of Bi82+

The self-energy contribution to the hyperfine splitting of the ground state of Bi⁸²⁺ is calculated for a point nucleus. It is found that the theoretical value of the wavelength of the ground-state hyperfine-splitting transition of ²⁰⁹Bi⁸²⁺ is λ=244(1) nm and is in good agreement with experiment. Pis’ma Zh. éksp. Teor. Fiz. 63, No. 5, 309–310 (10 March 1996) Published in English in the original Russian journal. Edited by Steve Torstveit.