1. Multiwavelength Systematics of O-Type Spectra Nolan R. Walborn Space Telescope Science Institute Chandra X-Ray Spectroscopy Workshop, July 11-13, 2007 X-Ray Collaborators: Wayne Waldron, Joy Nichols, Nancy Evans, Nathan Miller Optical/UV Collaborators: Ian Howarth, Danny Lennon, Alex Fullerton

2. Walborn Diagram

3. Optical O Main Sequence N IV/III He II/I

4. UV O Main Sequence (No Si IV)

5. UV OB Main Sequence (No Si IV)

6. Optical Early O Supergiant Sequence N IV/III

7. Optical OB Supergiant Sequence Si IV/III/II

8. UV O Supergiant Sequence Si IV!

9. UV B Supergiant Sequence Si IV!

10. FUV O Supergiant Sequence (O VI, C III)

11. Optical O Luminosity Sequence (He II λ4686, N III λ4640)

12. UV O Luminosity Sequence (Si IV! 45 eV)

13. FUV O Luminosity Sequence (S IV 47 eV, C III 48 eV, P V 65 eV but low abundance!)

14. X-Ray OB Supergiant Sequence Si XIV/XIII Mg XII/XI Ne X/IX O VIII/VII

15. X-Ray OB Main Sequence Si XIV/XIII Mg XII/XI Ne X/IX O VIII/VII

16. X-Ray O Luminosity Sequences

17. X-Ray O Luminosity Sequences

19. X-Ray OB Peculiar Objects