EGAS41 - Swansea University

41 st EGAS CP 23 Gdańsk 2009
Hyperfine quenching of 3s3p 3 P 0 , 3 P 2 level of Mg-like ions
H.H. Kang 1,2 , J.G. Li 1,2 , C.Z. Dong 1,2,∗ , P. Jönsson 3 , G. Gaigalas 4,5
1 College of Physics and Electronic Engineering, Northwest Normal University,
Lanzhou 730070, China
2 Joint Laboratory of Atomic Physics, NWNU & IMP CAS, Lanzhou 730070, China
3 Nature, Environment, Society, Malmö University, Malmö S-20506, Sweden
4 Department of Physics, Vilnius Pedagogical University, Studentu 39,
Vilnius LT-08106, Lithuania
5 Institute of Theoretical Physics and Astronomy, A. Goštauto 12, Vilnius LT-01108, Lithuania
∗ Corresponding author: Dongcz@nwnu.edu.cn
Theoretical investigations on hyperfine quenching of metastable levels 3s3p 3 P 0 and 3 P 2
of Mg-like ions between Z = 13 − 78 have been performed [1, 2] using Grasp2K package
[3] based on the multi-configuration Dirac-Fock method. Electron correlation, Breit interaction
and QED effects were taken into account systematically. Hyperfine quenching
rates of 3s3p 3 P 0 level were compared with other theoretical [4, 5] and experimental values
[6]. The present calculated probability of 4.327 × 10 −2 s −1 for 27 Al + is in good agreement
with recent the experimental measurement of 4.854 × 10 −2 s −1 [6]. Furthermore, a fitting
formula scaling in Z was obtained, which was presented in Fig.1 (a). In addition, it was
found that the lifetime of 3s3p 3 P 2 level is sensitive to the hyperfine quenching at the
beginning of the isoelectronic sequence as shown in Fig.1 (b).
4.0
3.2
2.4
1.6
(a)
10 7
10 5
HIT
M1
M2
10 9 9/2
(b)
Log(A) (s -1 )
0.8
0.0
-0.8
-1.6
-2.4
A(I=1/2)
A(I=5/2)
A(I=3/2)
A(I=7/2)
Experimental value[6]
A el
A el = 1.087*10 -11 Z 7.8004
Fitting by Brage[5]
10 15 20 25 30 35 40 45 50 55 60 65 70 75 80
Z
log(A)(s -1 )
10 3
10 1
10 -1
10 -3
7/2
5/2
3/2
1/2
10 -5
10 15 20 25 30 35 40 45 50 55 60 65 70 75 80
Z
Figure 1: Logarithm of hyperfine induced transition rates A together with reduced hyperfine
induced transition rates A el . (a): hyperfine quenching of 3 P 0 level, other theoretical and experimental
results were shown; (b): hyperfine quenching 3 P 2 level compared with other main decay
rates.
References
[1] H.H. Kang, J.G. Li, C.Z. Dong, P. Jönsson, G. Gaigalas, J. Phys. B (Submitted)
(2009)
[2] H.H. Kang, J.G. Li, C.Z. Dong, P. Jönsson, G. Gaigalas, (to be submitted) (2009)
[3] P. Jönsson, X. He, Ch. Froese Fischer, I.P. Grant, Comput. Phys. Commun 177 597
(2007)
[4] J.P. Marques, F. Parente, P. Indelicato, At. Data Nucl. Data Tables 55 157 (1993)
[5] T. Brage, et al., ApJ 500 507 (1996)
[6] T. Rosenband, P.O. Schmidt, D.B. Hume, et al. Phys. Rev. Lett, 98, 220801 (2007)
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