1. Stark Spectroscopy of PbF molecule Tao Yang, Priyanka Milinda Rupasinghe, James Coker, Haoquan Fan, John Moore-Furneaux, Neil E. Shafer-ray Homer L. Dodge Department of Physics and Astronomy University of Oklahoma June 23 th, 2011

2. Table of Contents  History and motivation  PbF as a probe for e-EDM  208 Pb 19 F Stark spectroscopy  Summary

3. History and motivation The existence of the permanent e-EDM results in violations of two fundamental symmetries: Charge- Parity Symmetry and Time Reversal Symmetry. 1950195319561964 2011 Future How time flies * J. J. Hudson, D. M. Kara, I. J. Smallman, B. E. Sauer, M. R. Tarbutt and E. A. Hinds, Nature 473, 493–496 (2011).

4. PCT --+ +-- +-- T (CP)

5. We do not measure e-EDM directly, however, we measure EDM of an atom or a molecule instead. PbF as a probe for e-EDM E ext E eff

6. In practice, we need only a 8kV/cm to get Eeff= ~30GV/cm 10 -30 -15 0 E lab (kV/cm) E eff (GV/cm)

7. Possible problem with PbF as a probe of an e-EDM is MAGNETIC MOMENT DEPENDS ON THE MAGNITUDE OF E.

8. PbF beam E0E0 Optical Alignment of PbF Optical Probe of PbF To gain sensitivity to the e-EDM,

9. Pseudocontinuous resonant enhanced multiphoton ionization (pc-REMPI) 208 Pb 19 F Stark spectroscopy

10. PbF + e-e- MCP multichannel scalar 476nm or 468nm 76MHz 6ps 800 mW 436nm or 444nm cw 10MHz ---P. Sivakumar, C. P. McRaven, P. M. Rupasinghe, T. Yang, N. E. Shafer-Ray, Trevor J. Sears and Gregory E. Hall, Molecular Physics: An International Journal at the Interface Between Chemistry and Physics, Volume 108, Issue 7 & 9 (2010).

11. Experimental configuration

12. ---P. Sivakumar, C. P. McRaven, P. M. Rupasinghe, T. Yang, N. E. Shafer-Ray, Trevor J. Sears and Gregory E. Hall, Molecular Physics: An International Journal at the Interface Between Chemistry and Physics, Volume 108, Issue 7 & 9 (2010).

13. Numerical solution for the hyperfine and Stark interaction eigenvalues of the effective spin-rotational Hamiltonian ---R. A. Frosch and H. M. Foley, Phys. Rev. 88, 1337–1349 (1952) ---M.G. Kozlov, V.I.Fomichv, Yu Yu Dmitriev, L.N. Labzovsky and A.V. Titov, J. Phys. B: At. Mol. Phys. 20(1987) ---M.G. Kozlov, L.N. Labzowsky, J. Phys. B: At. Mol. Phys. 28(1995)

14. Simulation of Stark shift on two branches

15. ---Lukas D. Alphei, Jens-Uwe Grabow, A. N. Petrov, Richard Mawhorter, Benjamin Murphy, Alexander Baum, Trevor J. Sears, T. Yang, P. M. Rupasinghe, C. P. McRaven and N. E. Shafer-Ray, Phys. Rev. A 83, 040501(R) (2011). This work(66% C.L.) Ref. Y.Y. Dmitriev, et al, Phys. Lett. A 167, 280(1992) Ref. K. I. Baklanov, et al, Phys.Rev.A 82, 060501 (2010) 4.62 D4.26 D ——2.51 D

16. Simulation of Stark shift on two branches Q fe (1/2) Ability to do state-selective ionization In an strong electric field depends critically on the curvature of these lines!

17. IT WORKS!!! Expected Spectra of the Q[1/2] Transition in an E Field (95% Uniformity)

18. ---P. Sivakumar, C. P. McRaven, P. M. Rupasinghe, T. Yang, N. E. Shafer-Ray, Trevor J. Sears and Gregory E. Hall, Molecular Physics: An International Journal at the Interface Between Chemistry and Physics, Volume 108, Issue 7 & 9 (2010).

19. Summary  PbF is a promising candidate for measuring the e-EDM.  We have measured the electric dipole moment of the X 1 and A states.  The dipole moments of the X 1 and A states allow for an F=1 to F=1 transition that is relatively immune to variations in electric field. This allows for a magnetic field free measurement of the e-EDM eliminating many possible sources of systematic error. This work(66% C.L.) Ref. Y.Y. Dimitiev, et al, Phys. Lett. A 167, 280(1992) Ref. K. I. Baklanov, et al, Phys.Rev.A 82, 060501 (2010) 4.62 D4.26 D 2.51 D

20. Professors Neil E. Shafer-ray, John Moore-Furneaux Graduate students Priyanka Milinda Rupasinghe, Tao Yang, James Coker, Haoquan Fan Undergraduate students Jacob Stinnett, Jeffery Gillean Lab members Last Generation of graduate students Poopalasingam Sivakumar, Christopher P. McRaven

21. Acknowledgements Supported by the National Science Foundation and the University of Oklahoma’s Office of the Vice President for Research. Thank you!