0000000000303251
AUTHOR
V. Rahkonen
showing 6 related works from this author
An isomeric 19+ state of the $$\pi h_{{9 \mathord{\left/ {\vphantom {9 2}} \right. \kern-\nulldelimiterspace} 2}}^2 i_{1{3 \mathord{\left/ {\vphantom…
1978
Usingα-particles of energies 35–51 MeV and in-beam conversion electron andγ-spectroscopy techniques, a 4.0±1.7 μs core-excited 19+ isomeric state in210At with ag-factor of 0.737±0.025 has been observed at an excitation energy of 4027.7 keV. The 19+ state is suggested to have the $$\pi h_{{9 \mathord{\left/ {\vphantom {9 2}} \right. \kern-\nulldelimiterspace} 2}}^2 i_{1{3 \mathord{\left/ {\vphantom {3 2}} \right. \kern-\nulldelimiterspace} 2}} vg_{{9 \mathord{\left/ {\vphantom {9 2}} \right. \kern-\nulldelimiterspace} 2}} (j^{ - 2} )_{0^ + }$$ configuration with maximum alignment of the angular momenta. The total two-particle core polarization due to theh 9/2 andi 13/2 protons and theg 9/2 n…
On the Yrast Structure of206Po
1986
Excited states in 206Po with spins up to 16 were identified through reactions with 3He- and α-particles on targets of 206Pb. Level and transition properties were studied using conventional in-beam γ-ray and conversion electron spectroscopy. The half-life of the yrast 9- state, identified as the neutron two-quasiparticle state ν(f5/2-1i13/2-1)9-, was determined as 1.0 μs. No other isomers, besides the previously known isomeric 8+ state, were observed. The excited states are classified within the shell-model description. Transition probabilities are discussed.
Low- and medium-spin states in theN=124 isotones208Po and209At
1985
Excited levels in208Po and209At were populated in the reactions (p, 2n) and (3He, 3n), and208Po also in the EC-decay of the208At ground state, which was produced in the209Bi(3He, 4n) reaction. The experimental procedures comprised gamma-ray excitation functions,γ- γ coincidences, as well as gamma-ray angular distribution and conversionelectron measurements, both on- and off-line. The properties of about twenty-five levels in each nuclide were studied. In208Po the energy of the 8+→6+ transition could be determined to be 4.0±0.2keV and the 8+ state thus has an excitation energy of 1,528 keV. The effective quadrupole charge of theh 9/2 proton can be derived ase eff(τ h 9/2)=1.69(15)e. For the …
In-beam study of high-spin states in199,200,201Po and systematical features of Z=84 polonium isotopes
1985
Excited states in199,200,201Po were populated in the reactions12C+194Pt and12C+195Pt. The subsequentγ-radiation was studied using conventional in-beam spectroscopic methods. States with spins up to (29/2), 18 and ≧35/2ħ, respectively, were populated in the three nuclides. Three isomeric states with the following half-lives were observed in200Po:T1/2(8+)=90(15) ns,T1/2(11−)=120(20) ns andT1/2(12+)=267(4) ns. The structure of the excited states was interpreted within the framework of the spherical shell model. The three isomers are suggested to be two-quasiparticle states with configurationsπ(h22)8J, π(h9i13/2)11- and v(i1 3/2−2)12+. A self-consistent Hartree-Fock calculation was performed to…
Evidence for Two-Nucleon Polarization in the π(h9/2i13/2)11- ν(j-2)0+ Level in 208Po
1974
From in-beam gamma-ray spectroscopy measurements on the 208Pb(α, 4n)208Po reaction using the Stockholm 225-cm cyclotron, we have concluded that there is an 11-, 8 ns isomeric state in 208Po, which lies 1 175 keV above the π(h 9/2 2)8+ state and that this isomeric state should have the configuration π(h 9/2 i 13/2)11- ν(j -2)0+. Calculations based on the use of empirical two-particle interactions give a position of the 11- level which deviates by about + 100 keV from the experimentally found position. It is suggested that this deviation is mainly due to the difference in the polarization of the 206Pb-and 208Pb-cores by the two aligned h 9/2 and i 13/2 protons.
On the yrast two proton-two neutron hole states in208Po
1978
High-spin levels in208Po, populated in the208Pb(α,4n)-reaction, were studied usingα-particles in the energy region 41–51 MeV. The energies of levels above the 6+ level have an uncertainty of about 10 keV due to the fact that the 8+→6+ transition has not been observed so far, but this transition has previously been established to be converted neither in theK-shell nor in theL-shells. It was found that the yrast cascade ofγ-rays from a 19+ level at 5896+e keV feeds levels of lower spin which all can be explained as originating from two proton-two neutron hole configurations. In the higher part of the cascade it is mainly the neutron holes which change their configuration, while the lower part…