GANIL

[paper] First g(2+) measurement on neutron-rich ⁷²Zn, and the high-velocity transient field technique for radioactive heavy-ion beams

First g(2+) measurement on neutron-rich ⁷²Zn, and the high-velocity transient field technique for radioactive heavy-ion beams

E. Fiori et al.

doi: 10.1103/PhysRevC.85.034334

The high-velocity transient-field (HVTF) technique was used to measure the g factor of the 2⁺ state of ⁷²Zn produced as a radioactive beam. The transient-field strength was probed at high velocity in ferromagnetic iron and gadolinium hosts using ⁷⁶Ge beams. The potential of the HVTF method is demonstrated and the difficulties that need to be overcome for a reliable use of the TF technique with high-Z, high-velocity radioactive beams are revealed. The polarization of K-shell vacancies at high velocity, which shows more than an order of magnitude difference between Z=20 and Z=30 is discussed. The g-factor measurement hints at the theoretically predicted transition in the structure of the Zn isotopes near N=40

Mar 29, 2012 by Theo g factor 0

[paper] g factor of the ⁴⁴Cl ground state: Probing the reduced Z=16 and N=28 gaps

g factor of the ⁴⁴Cl ground state: Probing the reduced Z=16 and N=28 gaps

M. De Rydt et al.

doi: 10.1103/PhysRevC.81.034308

The g factor of the ⁴⁴Cl ground state is measured at the LISE fragment separator at the Grand Acclérateur National d’Ions Lourds (GANIL) using the β nuclear magnetic resonance technique, resulting in g(⁴⁴Cl)=(-)0.2749(2). An analysis of the g factor value and of the theoretical level scheme in the shell-model framework reveals the presence of odd-proton s_1/2 configurations and neutron excitation across the N=28 shell gap in the ground state of ⁴⁴Cl. In addition, the measured g factor strongly supports a 2^– spin assignment for the ⁴⁴Cl ground state.

Mar 19, 2010 by Theo experiment g factor theory 0

[paper] g factor of the exotic N=21 isotope ³⁴Al: probing the N=20 and N=28 shell gaps at the border of the "island of inversion"

g factor of the exotic N=21 isotope ³⁴Al: probing the N=20 and N=28 shell gaps at the border of the "island of inversion"

P. Himpe et al.

doi: 10.1016/j.physletb.2007.11.017

For the first time the g factor of an isotope beyond N=20 near the "island of inversion" has been measured. A ³⁴Al radioactive beam was produced in a one-neutron pickup reaction on a ³⁶S primary beam at 77.5 MeV/u, providing a large spin-polarization for application of the β-Nuclear Magnetic Resonance (β-NMR) method. The measured g factor of ³⁴Al, |g|=0.539(2), combined with results from earlier β-decay studies, allows to firmly assign a ground state spin/parity 4⁻. Comparison to large scale shell model calculations reveals that a dominant amount of intruder components is needed in the ³⁴Al wave function to account for the observed large magnetic moment μ=(+)2.156(16)μ_N. This reveals Z=13 to be a true "transition number" between the normal Z=14 Si isotopes and the abnormal Z=12 Mg isotopes. The sensitivity of this odd–odd ground state dipole moment to the N=20, as well as the N=28 gap, reveals that both are significantly reduced, despite Z=13 being outside the conventional island of inversion.

Jan 10, 2008 by Theo experiment g factor 0

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