In-beam quadrupole interaction measurements by level mixing resonance

Static Quadrupole Moment of the Five-QuasiparticleK=352Isomer inW1

“…[11][12][13]. It has been shown that the method gives results that are compatible with other techniques and in many cases more appropriate to apply [15,16].…”

“…They were in-beam implanted into a thick Tl polycrystalline foil, which served as a levelmixing spectroscopy (LEMS) host and as a beam stopper. The experiments were performed at the CYCLONE cyclotron at Louvain-la-Neuve, using the LEMS technique [11][12][13]. The experimental setup consists of a split-coil 4.4 T superconducting magnet, a target holder, allowing precise temperature control at the target position in the interval 4 -600 K, and 4 Ge detectors, which monitor the target through the holes of the magnet.…”

Nuclear magnetic and quadrupole moments for nuclear structure research on exotic nuclei

“…When the tilt angle β is small (<20˚), the last term in the Hamiltonian (5.11) can be considered as a small perturbation on the unperturbed energy levels (5.12). The eigenstates and energy of the total Hamiltonian can be derived in first-order quasi-degenerate perturbation theory [171] in a 'two-level' approximation [170,172,104]. This means that, in a first approximation, we can assume that the energy of the perturbed states is similar to the energy of the unperturbed states except for two nearly-degenerate energy levels.…”

“…The mixing parameter R depends on the non-diagonal matrix element [172] which induces an interaction between the |m and |m levels. This perturbation is proportional to:…”

“…At the level mixing field, determined by ω L = 3(m + m )ω Q cos β, the mixing parameter is R = 1 and the two levels are fully mixed [172]. One can calculate in a density matrix formalism that the level populations have become equal, as demonstrated further in equation (5.23).…”