Magnetic moment of the 12+-isomer in192Pb

The magnetic moment of the 12⁺-isomer in¹⁹²Pb has been measured using the PAD technique. The isomer was populated by¹⁵⁶Gd (⁴⁰Ar,4n)-reaction with a pulsed⁴⁰Ar-beam of 185 MeV. The result for the g-factor is g=?0.173(2) after corrections for Knight shift and diamagnetism. As this state has a rather pure Ν (i13/2)^2? configuration, the value reflects directly the Ν i13/2 orbital. It shows a decrease towards the more neutron deficient isotopes attributed to the reduced core polarisation as a result of decreasing occupation of the i13/2 neutron shell. In comparison with a core polarisation calculation good agreement was found.     

Knight shift of sp-elements in bismuth

A large negative term in the Knight shift has been found for a number of open p-shell elements of the 5th and 6th period in the host Bi which disappears at the p-shell closure.The authors would like to acknowledge the fruitful discussions with R.E. Watson.     

The half-lives of the first and second excited states in 66Ga

The half-lives of the first and second excited states at 43.9 and 66.3 keV in ⁶⁶Ga were determined by measuring the time dependence of the 43.9 and 22.4 keV γ-transition intensities. The levels in ⁶⁶Ga were populated by the ⁶⁶Za(p, n)⁶⁶Ga and ⁶³Cu(α, n)⁶⁶Ga reactions. The results are T_{$\text{1}\text{2}$}(43.9 keV) = 16(4) ns and T_{$\text{1}\text{2}$}(66.3 keV) = 23(2) ns. A g-factor measurement reported in the literature is reanalysed.     

Electric quadrupole interaction of 212Rn isomers in Bi

The electric quadrupole interaction of the ²¹² Rn 8⁺ and 6⁺ isomers in a Bi single crystal was measured. The experimental results together with a shell-model calculation of the quadrupole moments provide a calibration of the electric field gradient for Rn impurities in Bi, to be used in future quadrupole-moment measurements of Rn isomers. A two-level analysis procedure was employed for the combined data of the 8⁺ and 6⁺ isomers.     

Time-differential observation of quadrupole interactions following recoil implantation of a Ge-probe into Cd,In, Sn,and Sb

We have measured the quadrupole interactions of excited⁶⁷Ge nuclei in the polyvalent metals Cd, In, Sn, and Sb. The experiments have been performed by the time-differential angular distribution technique, following the reaction⁶⁴Zn(, n)⁶⁷Ge to produce and implant the Ge nuclei into the different metals (DIMPAD). A sandwich target system is used, which allows the application of the DIMPAD-technique for low recoil energies. The extracted electric field gradients are found to depend on the host metal as well as on the solute Ge, an interpretation is suggested on the basis of charge screening effects.     

Strong probe atom dependence of the electric field gradient in Bismuth

The nuclear quadrupole interaction of the 8⁺ isomers in^{206, 208}Po was measured in the semimetallic host Bi. The comparison of the extracted electric field gradient eq for PoBi with the values for the neighboring elements Bi and Pb as probe atoms in Bi reveals a very drastic increase from Pb to Bi and to Po by an order of magnitude: eq_PbBi eq_BiBi eq_PoBi =1.64(10)4.8(3)16(2)(all values at room temperature in units of 10¹⁷ V/cm²). This behavior is discussed in terms of the changing number of outerp-electrons of the probe atoms.