1 / 32

Asteroseismology of Gamma Doradus, Beta Cephei, Delta Scuti and other ‘heat-engine’stars

Asteroseismology of Gamma Doradus, Beta Cephei, Delta Scuti and other ‘heat-engine’stars. J ørgen Christensen-Dalsgaard Institut for Fysik og Astronomi, Aarhus Universitet Dansk AsteroSeismologisk Center. Mode excitation or damping. Growth rate: amplitude / exp( h t), with.

bridie
Download Presentation

Asteroseismology of Gamma Doradus, Beta Cephei, Delta Scuti and other ‘heat-engine’stars

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Asteroseismology of Gamma Doradus, Beta Cephei, Delta Scuti and other ‘heat-engine’stars Jørgen Christensen-Dalsgaard Institut for Fysik og Astronomi, Aarhus Universitet Dansk AsteroSeismologisk Center

  2. Mode excitation or damping Growth rate: amplitude / exp(h t), with In nonadiabatic region, d L ' constant

  3. Simplified excitation (J. P. Cox 1964) Too hot

  4. Simplified excitation Too cold

  5. Simplified excitation Just right!!

  6. Note:Decreasing Teff! increasing mb! increasing P for a given opacity bump Location of instability region

  7. Opacity bumps Pamyatnykh (1999; Acta Astron. 49, 119)

  8. Double-mode Cepheids

  9. Petersen diagram (J.O. Petersen 1973; Astron. Astrophys 27, 89) Double-mode Cepheids P0! tdyn / (R3/M)1/2 P0 , P1! R, M???

  10. Old opacity New (OPAL) opacity Track along instability strip P0! tdyn / (R3/M)1/2

  11. Massive pulsators

  12. Excitation calculation Pamyatnykh (1999; Acta Astron. 49, 119)

  13. Work integrals b Cephei SPB d Scuti

  14. l = 0 l = 1 l = 1 Asteroseismologi of b Ceph stars n Eridani De Ridder et al. (2004; MNRAS 351, 324)

  15. Avoided crossings Models of n Eridani Pamyatnykh et al. (2004; 350, 1022)

  16. d Scuti stars

  17. Excitation d Scuti b Cephei Pamyatnykh (2000; ASP. Conf. Ser. 210, 215)

  18. Excited modes d Scuti b Cephei

  19. Instability regions Pamyatnykh (2000; ASP. Conf. Ser. 210, 215)

  20. Mode selection

  21. Breger (1995; ASP Conf. Ser. 76, 596) Analysis techniques

  22. FG Virginis Breger et al. (2005; Astron. Astrophys. 435, 955)

  23. FG Virginis frequencies Breger et al. (2005)

  24. FG Virginis frequencies Breger et al. (2005)

  25. FG Virginis amplitude distribution Breger et al. (2005)

  26. FG Virginis frequency interpretation No rotation With rotation, nnlm = nnl0 + m W/2 p Templeton et al. (2001; ApJ 563, 999)

  27. Altair: the brightest d Scuti star Observations with the WIRE satellite Buzasi et al. (2005; ApJ 619, 1072)

  28. g Doradus stars

  29. Very slow pulsations Poretti et al. (2002; Astron. Astrophys. 384, 513)

  30. Very extended observations Aerts et al. (2004; Astron. Astrophys. 415, 1079)

  31. Instability region Warner et al. (2003; ApJ 593, 1049)

  32. Convective blocking Guzik et al. (2002; ASP Conf. Ser. 259, 502)

More Related