Abstract
The electric E1 and magnetic M1 dipole responses of the N= Z nucleus 24 Mg were investigated in an inelastic photon scattering experiment. The 13.0 MeV electrons, which were used to produce the unpolarised bremsstrahlung in the entrance channel of the 24 Mg(γ, γ′) reaction, were delivered by the ELBE accelerator of the Helmholtz-Zentrum Dresden-Rossendorf. The collimated bremsstrahlung photons excited one Jπ= 1 - , four Jπ= 1 + , and six Jπ= 2 + states in 24 Mg. De-excitation γ rays were detected using the four high-purity germanium detectors of the γ ELBE setup, which is dedicated to nuclear resonance fluorescence experiments. In the energy region up to 13.0 MeV a total B(M1)↑=2.7(3)μN2 is observed, but this N= Z nucleus exhibits only marginal E1 strength of less than ∑ B(E1) ↑ ≤ 0.61 × 10 - 3 e 2 fm 2 . The B(Π1,1iπ→21+)/B(Π1,1iπ→0gs+) branching ratios in combination with the expected results from the Alaga rules demonstrate that K is a good approximative quantum number for 24 Mg. The use of the known ρ2(E0,02+→0gs+) strength and the measured B(M1,1+→02+)/B(M1,1+→0gs+) branching ratio of the 10.712 MeV 1 + level allows, in a two-state mixing model, an extraction of the difference Δβ22 between the prolate ground-state structure and shape-coexisting superdeformed structure built upon the 6432-keV 02+ level.
Original language | English |
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Article number | 198 |
Journal | European Physical Journal A |
Volume | 59 |
Issue number | 9 |
DOIs | |
State | Published - Sep 2023 |
Bibliographical note
Publisher Copyright:© 2023, The Author(s).
ASJC Scopus subject areas
- Nuclear and High Energy Physics