1. On the 1s2s2p 4 P o 5/2 metastable state in the Li-like ions P. Palmeri, P. Quinet, C. Mendoza, M. Godefroid, N. Vaeck and P. Indelicato

2. Outlook Introduction Models used Results Conclusion

3. Introduction Decay properties of 1s2s2p 4 P o 5/2 is a workbench for magnetic interactions  Good case for comparing the Breit-Pauli approximation with models based on the Dirac equation !

4. Decay scheme

5. Codes used Breit-Pauli approximation: SUPERSTRUCTURE (M1 & M2) AUTOSTRUCTURE (Auger & M1) Dirac equation: GRASP (M1 & M2) MDF-GME (M1, M2 & Auger)

6. SUPER/AUTOSTRUCTURE Schrodinger equation using a scaled TFD potential, V( r). Magnetic interactions (1 & 2-body): spin-orbit, spin-other-orbit, spin-spin, spin-contact, orbit- orbit. CI: single and double-excitations up to n=3 Orthogonal orbitals DW approximation for the Auger Z=3,4,6,7,8,9,10,12,13,14,16,18,20,22,23,25,26, 30,36,54,67,80,92

7. GRASP Multiconfiguration Dirac-Fock method Breit interaction + QED corrections CI: S&D-excitations up to n=3 Orthogonal orbitals Z=4,6,7,8,9,10,12,13,14,16,18,20,22,23,25, 26,30,36,54,67,80,92

8. MDF-GME MCDF method Breit interaction + QED corrections CI: S&D-excitations up to n=4 (M1&M2); up to n=5 (Auger) Non-orthogonal orbitals DW approximation Z=16,18,26

9. Decay rates along the sequence

10. Lifetime: comparison with experiment

11. Auger rate: comparison with other models

12. M2 rate : comparison with other models

13. M1 rate: comparison with other models

14. Relativistic correction to the M1 transition operator IonSS* A (s -1 ) SS A (s -1 ) GRASP A (s -1 ) MDF A (s -1 ) S XIV6.37E-11.33E+61.34E+62.10E+6 Ar XVI1.524.46E+64.54E+66.26E+6 Fe XXIV6.22E+21.94E+82.00E+82.22E+8

15. Conclusion Breakdown of the B-P approximation (discord with Dirac theory > 20%): M1 for Z > 36 (Kr) M2 for Z > 54 (Xe) Auger for Z > 80 (Pb)