1. e-mail:elyratzi@phys.uoa.gr edanezis@phys.uoa.gr http://www.cc.uoa.gr/fasma University of Athens, Faculty of Physics, Department of Astrophysics, Astronomy and Mechanics Astronomical Observatory of Belgrade Long term variability of the coronal and post – coronal regions of the Oe star HD 149757 (ζ Oph) Antoniou, A. 1, Danezis, E. 1, Lyratzi, E. 1, Nikolaidis, D. 1, Popović, L. Č. 2 & Dimitrijević, M. S. 2 1. University of Athens, Faculty of Physics, Department of Astrophysics, Astronomy and Mechanics, Panepistimioupoli, Zographou 157 84, Athens – Greece. 2. Astronomical Observatory, Volgina 7, 11160 Belgrade, Serbia.

2. e-mail:elyratzi@phys.uoa.gr edanezis@phys.uoa.gr http://www.cc.uoa.gr/fasma University of Athens, Faculty of Physics, Department of Astrophysics, Astronomy and Mechanics Astronomical Observatory of Belgrade C IV N IV N V λ 1548.155 Å λ 1550.774 Å λ 1238.821 Å λ 1242.804 Å λ 1718.80 Å

3. e-mail:elyratzi@phys.uoa.gr edanezis@phys.uoa.gr http://www.cc.uoa.gr/fasma University of Athens, Faculty of Physics, Department of Astrophysics, Astronomy and Mechanics Astronomical Observatory of Belgrade Vrot, Vrad, Vrand: Constant with time Rotational Velocities : a component: 1400 km/s b component: 950 km/s Radial Velocities : a component: -800 km/s b component: -700 km/s Random Velocities : a component: 320 km/s b component: 90 km/s C IV regions

4. e-mail:elyratzi@phys.uoa.gr edanezis@phys.uoa.gr http://www.cc.uoa.gr/fasma University of Athens, Faculty of Physics, Department of Astrophysics, Astronomy and Mechanics Astronomical Observatory of Belgrade Column Density (CD) in 10 10 cm -2 of each one of the C IV resonance lines for the independent density regions of matter which create the satellite components. λ 1548.155 Å a component: 2.15×10 10 cm -2 b component: 0.72×10 10 cm -2 λ 1550.774 Å a component: 1.98×10 10 cm -2 b component: 0.66×10 10 cm -2

5. e-mail:elyratzi@phys.uoa.gr edanezis@phys.uoa.gr http://www.cc.uoa.gr/fasma University of Athens, Faculty of Physics, Department of Astrophysics, Astronomy and Mechanics Astronomical Observatory of Belgrade N IV region GR method V rad, V rand, CD: Constant with time Radial Velocities : -47 km/s Random Velocities : 262 km/s Column Density : 1.09×10 10 cm -2

6. e-mail:elyratzi@phys.uoa.gr edanezis@phys.uoa.gr http://www.cc.uoa.gr/fasma University of Athens, Faculty of Physics, Department of Astrophysics, Astronomy and Mechanics Astronomical Observatory of Belgrade N V regions GR method V rad, V rand : Constant with time Radial Velocities : a component: -1138 km/s b component: -1374 km/s c component: -1450 km/s Random Velocities : a component: 797 km/s b component: 152 km/s c component: 71 km/s

7. e-mail:elyratzi@phys.uoa.gr edanezis@phys.uoa.gr http://www.cc.uoa.gr/fasma University of Athens, Faculty of Physics, Department of Astrophysics, Astronomy and Mechanics Astronomical Observatory of Belgrade Column Density (CD) in 10 10 cm -2 of each one of the N V resonance lines for the independent density regions of matter which create the satellite components. λ 1238.821 Å a component: 1.13×10 10 cm -2 b component: 0.25×10 10 cm -2 c component: 0.07×10 10 cm -2 λ 1242.804 Å a component: 1.03×10 10 cm -2 b component: 0.23×10 10 cm -2 c component: 0.06×10 10 cm -2

8. e-mail:elyratzi@phys.uoa.gr edanezis@phys.uoa.gr http://www.cc.uoa.gr/fasma University of Athens, Faculty of Physics, Department of Astrophysics, Astronomy and Mechanics Astronomical Observatory of Belgrade A statistical study of physical parameters of the C IV density regions in 20 Oe stars Antoniou, A. 1, Danezis, E. 1, Lyratzi, E. 1, Nikolaidis, D. 1, Popović, L. Č. 2 & Dimitrijević, M. S. 2 1. University of Athens, Faculty of Physics, Department of Astrophysics, Astronomy and Mechanics, Panepistimioupoli, Zographou 157 84, Athens – Greece. 2. Astronomical Observatory, Volgina 7, 11160 Belgrade, Serbia.

9. e-mail:elyratzi@phys.uoa.gr edanezis@phys.uoa.gr http://www.cc.uoa.gr/fasma University of Athens, Faculty of Physics, Department of Astrophysics, Astronomy and Mechanics Astronomical Observatory of Belgrade

10. e-mail:elyratzi@phys.uoa.gr edanezis@phys.uoa.gr http://www.cc.uoa.gr/fasma University of Athens, Faculty of Physics, Department of Astrophysics, Astronomy and Mechanics Astronomical Observatory of Belgrade Rotational Velocities : a component: 1458 km/s b component: 821 km/s c component: 251 km/s d component: 133 km/s e component: 65 km/s Radial Velocities : a component: -2066 km/s b component: -1743 km/s c component: -1235 km/s d component: -469 km/s e component: -80 km/s

11. e-mail:elyratzi@phys.uoa.gr edanezis@phys.uoa.gr http://www.cc.uoa.gr/fasma University of Athens, Faculty of Physics, Department of Astrophysics, Astronomy and Mechanics Astronomical Observatory of Belgrade Random Velocities : a component: 187 km/s b component: 163 km/s c component: 130 km/s d component: 108 km/s e component: 56 km/s FWHM : a component: 13.0 Å b component: 6.2 Å c component: 2.2 Å d component: 1.2 Å e component: 0.4 Å

12. e-mail:elyratzi@phys.uoa.gr edanezis@phys.uoa.gr http://www.cc.uoa.gr/fasma University of Athens, Faculty of Physics, Department of Astrophysics, Astronomy and Mechanics Astronomical Observatory of Belgrade Absorbed Energy (E) λ 1238.821 Å a component: 5.18 eV b component: 3.21 eV c component: 1.39 eV d component: 0.53 eV e component: 0.24 eV λ 1242.804 Å a component: 4.76 eV b component: 2.85eV c component: 1.26 eV d component: 0.48 eV e component: 0.22 eV

13. e-mail:elyratzi@phys.uoa.gr edanezis@phys.uoa.gr http://www.cc.uoa.gr/fasma University of Athens, Faculty of Physics, Department of Astrophysics, Astronomy and Mechanics Astronomical Observatory of Belgrade Column Density (CD) λ 1238.821 Å a component: 5.65 ×10 10 cm -2 b component: 4.58 ×10 10 cm -2 c component: 3.65 ×10 10 cm -2 d component: 2.62 ×10 10 cm -2 e component: 1.17 ×10 10 cm -2 λ 1242.804 Å a component: 5.54 ×10 10 cm -2 b component: 4.39 ×10 10 cm -2 c component: 3.56 ×10 10 cm -2 d component: 2.56 ×10 10 cm -2 e component: 1.17 ×10 10 cm -2

14. e-mail:elyratzi@phys.uoa.gr edanezis@phys.uoa.gr http://www.cc.uoa.gr/fasma University of Athens, Faculty of Physics, Department of Astrophysics, Astronomy and Mechanics Astronomical Observatory of Belgrade The N IV region in the spectra of 20 Oe stars Antoniou, A. 1, Danezis, E. 1, Lyratzi, E. 1, Nikolaidis, D. 1, Popović, L. Č. 2 & Dimitrijević, M. S. 2 1. University of Athens, Faculty of Physics, Department of Astrophysics, Astronomy and Mechanics, Panepistimioupoli, Zographou 157 84, Athens – Greece. 2. Astronomical Observatory, Volgina 7, 11160 Belgrade, Serbia.

15. e-mail:elyratzi@phys.uoa.gr edanezis@phys.uoa.gr http://www.cc.uoa.gr/fasma University of Athens, Faculty of Physics, Department of Astrophysics, Astronomy and Mechanics Astronomical Observatory of Belgrade

16. e-mail:elyratzi@phys.uoa.gr edanezis@phys.uoa.gr http://www.cc.uoa.gr/fasma University of Athens, Faculty of Physics, Department of Astrophysics, Astronomy and Mechanics Astronomical Observatory of Belgrade Two levels of Vrad, Vrand, FWHM Radial Velocities First level: -350 and -150 km/s Second level: -70 km/s Random Velocities First level: 350 and 220 km/s Second level: 150 and 50 km/s FWHM First level: 5 and 3 Ǻ Second level: 2 and 1 km/s Ǻ

17. e-mail:elyratzi@phys.uoa.gr edanezis@phys.uoa.gr http://www.cc.uoa.gr/fasma University of Athens, Faculty of Physics, Department of Astrophysics, Astronomy and Mechanics Astronomical Observatory of Belgrade Two levels of Absorbed Energy and Column Density Absorbed Energy (E) First level: 2 and 1.2 eV Second level: 0.6 and 0.4 eV Column Density (CD) First level: 4.5×10 10 cm -2 and 3×10 10 cm -2 Second level: 2.5×10 10 cm -2

18. e-mail:elyratzi@phys.uoa.gr edanezis@phys.uoa.gr http://www.cc.uoa.gr/fasma University of Athens, Faculty of Physics, Department of Astrophysics, Astronomy and Mechanics Astronomical Observatory of Belgrade Investigation of the post coronal density regions of Oe stars, through the N V UV resonance lines Antoniou, A. 1, Danezis, E. 1, Lyratzi, E. 1, Nikolaidis, D. 1, Popović, L. Č. 2 & Dimitrijević, M. S. 2 1. University of Athens, Faculty of Physics, Department of Astrophysics, Astronomy and Mechanics, Panepistimioupoli, Zographou 157 84, Athens – Greece. 2. Astronomical Observatory, Volgina 7, 11160 Belgrade, Serbia.

19. e-mail:elyratzi@phys.uoa.gr edanezis@phys.uoa.gr http://www.cc.uoa.gr/fasma University of Athens, Faculty of Physics, Department of Astrophysics, Astronomy and Mechanics Astronomical Observatory of Belgrade

20. e-mail:elyratzi@phys.uoa.gr edanezis@phys.uoa.gr http://www.cc.uoa.gr/fasma University of Athens, Faculty of Physics, Department of Astrophysics, Astronomy and Mechanics Astronomical Observatory of Belgrade Vrot:1st level: 1800 and 1100 km/s 2nd level: 400 and 200 km/s Vrad:1st level: -2300 and -1500 km/s 2nd level: -500 and -100 km/s Vrand:1st level: 400 and 200 km/s 2nd level: 150 and 80 km/s FWHM: 1st level: 18 and 10 Å 2nd level: 6 and 2 Å

21. e-mail:elyratzi@phys.uoa.gr edanezis@phys.uoa.gr http://www.cc.uoa.gr/fasma University of Athens, Faculty of Physics, Department of Astrophysics, Astronomy and Mechanics Astronomical Observatory of Belgrade Two levels of Absorbed Energy (E) λ 1238.821 Å First level: 7 and 3 eV Second level: 1 and 0.5 eV λ 1242.804 Å First level: 6.3 and 2.7 eV Second level: 0.9 and 0.45 eV

22. e-mail:elyratzi@phys.uoa.gr edanezis@phys.uoa.gr http://www.cc.uoa.gr/fasma University of Athens, Faculty of Physics, Department of Astrophysics, Astronomy and Mechanics Astronomical Observatory of Belgrade Two levels of Column Density (CD) λ 1238.821 Å First level:5×10 10 cm -2 and 3×10 10 cm -2 Second level: 2.5×10 10 cm -2 λ 1242.804 Å First level: 4.45×10 10 cm -2 and 2.7×10 10 cm -2 Second level: 2×10 10 cm -2

23. e-mail:elyratzi@phys.uoa.gr edanezis@phys.uoa.gr http://www.cc.uoa.gr/fasma University of Athens, Faculty of Physics, Department of Astrophysics, Astronomy and Mechanics Astronomical Observatory of Belgrade Thank you!!!