Radiative decay probabilities of the(2s22p1/253s1/

Abstract

The radiative decay rates of the (2s 2 2p 5 1/2 3s 1/2 ) J =0 level in neonlike ions have been calculated for nuclear charges ranging from Z = 10 to Z = 110. The calculations include the magnetic dipole decay to the (2s 2 2p 5 3/2 3s 1/2 ) J =1 level, which is shown to be the dominant decay branch in low-Z and very-high-Z ions, as well as the two-electron, one-photon decays to the (2s 2 2p 5 3/2 3p 1/2 ) J =1 and (2s 2 2p 5 3/2 3p 3/2 ) J =1 levels, which dominate near Z = 50. We also take into account a small magnetic quadrupole decay branch to the (2s 2 2p 5 3/2 3s 1/2 ) J =2 level and calculate the total radiative lifetime of the (2s 2 2p 5 1/2 3s 1/2 ) J =0 level. The resulting values span over 15 orders of magnitude, and much of this range is accessible with modern atomic lifetime measurement techniques. In particular, we calculate a value of 1.6 × 10 4 s −1 for the radiative decay rate of the (2s 2 2p 5 1/2 3s 1/2 ) J =0 level in Fe XVII and show that the corresponding magnetic dipole transition has a measurable spectral intensity for electron densities below about 1 × 10 13 cm −3 .

L-shell x-ray emission from neonlike W64+

“…Finally, we note that the line width is purely instrumental. The temperature of the ions in EBIT-I has been measured both for heliumlike and neonlike ions [77][78][79][80] ordering given by JJ-coupling [48,51,81]. This is why the alphabetical ordering of lines 3A through 3G no longer follows the energy order established in iron and observed by Parkinson [66].…”

Theoretical Confirmation of the Low Experimental3C/3Df-Value Ratio in Fe xvii

“…The present Mod1, Mod2, and Mod4 radiative data are compared in Table IV with experiment and calculations performed in the past decade using a variety of numerical methods: relativistic CI [32]; many-body perturbation theory (MBPT) [32,33,35]; the flexible atomic code (FAC) [12,35]; multiconfiguration Dirac-Hartree-Fock combined with a relativistic CI method (MCDHF-RCI) [34]; and the same BPCI method as the present [36]. The Mod4 M2 A-value is in very good agreement with both experiment and previous theoretical estimates; however, the Mod4 M1 A-value is a little higher than experiment (still within the experimental uncertainty), Mod1, and Mod2 but in very good accord with the other theoretical data.…”

Proposal for observation of transitions induced by external magnetic fields mixing in the lower states: with an example from Fe X

“…Transitions induced by the presence of an external magnetic field (we will label these as MIT) were first observed by Beiersdorfer et al [1], through the 2p 5 3s 3 P 0 →2p 6 1 S 0 transition in neon-like Argon, in an electron beam ion trap (EBIT). This initiated a new field of investigation and the MITs were recognized not only as a disturbance or source of error in measurements of long lifetimes [2][3][4] but also a new and rather exotic way of probing the structure of ions [5][6][7][8][9][10][11][12][13]. In all of these works the mixing that drives the transition is in the upper states, something that is a common assumption in the search for 'unexpected transitions' [14,15].…”