Recoil-distance measurements of g-factors for 24Mg(21+) and 20Ne(21+)

Abstract

Time-differential recoil-into-vacuum measurements have been performed with a plunger on the first-excited 1 ~ = 2 + states of 24Mg and 2°Ne. The states were populated by the reactions 12C(t60, ct)2'*Mg and ~2C(~ 2C, ct)2°Ne. The measured anisotropy of the :t-7 angular correlation was greatly increased by means of a vertical slit on the annular particle detector. ionic electron configurations. Natural targets.

Nuclear physics experiments with in-beam fast-timing and plunger techniques

“…By the use of the well-defined hyperfine fields, together with efficient particle and γ-ray detection, the experimental g factor that obtained from the R(t) is g = 080009-8 0.538 (13) [14], in reasonable agreement with, but more precise than, the previous measurement, g = 0.51(2) [35]. Thus, the shell-model calculations consistently predict that the g factor of the first-excited state in the N = Z nucleus 24 Mg is increased from g = 0.5, and this experiment confirms these predictions for the first time.…”

“…From Ref. [14] In the traditional TDRIV technique [33,35], the interaction time is defined experimentally using a plunger device. As illustrated in Fig.…”

Nuclear g-factor measurement with time-dependent recoil in vacuum in radioactive-beam geometry

“…The useful hyperfine magnetic fields are the transient magnetic field (TF) [1] and the free-ion hyperfine fields of ions recoiling in vacuum (RIV) [2,3]. In the case of the RIV technique, as applied recently to heavy radioactive ion beams [4,5,6], the averaging of the hyperfine frequency over the different electronic configurations gives a quasiexponential dependence of the vacuum attenuation factors, G k , as a function of the lifetime of the state of interest.…”

“…A measurement of g(2 + ) in 24 Mg with the conventional technique was performed by Horstman et al [2] following the 12 C( 16 O,αγ) 24 Mg reaction. In that measurement only ∼ 15 % of the Mg ions exiting the target were in H-like charge state.…”

A priori calculations of hyperfine interactions in highly ionized atoms: g-factor measurements on aligned pico-second states populated in nuclear reactions

“…This fundamental approach requires detailed knowledge of the contributing J states, their magnetic hyperfine interaction strengths A(J) and the relative probabilities of the ionic charge states present in the recoil ion population. Pioneer attempts at such calculations have been made in the past for light elements [3,4] but this is the first approach to such a calculation valid for a wide range of elements and charge states. The calculation uses the Dirac-Hartree-Fock multi-configuration model coded as the GRASP package built up over the years by the groups at Oxford and Vanderbilt University and their collaborators.…”