1 / 31

The Structure of AGB Winds

The Structure of AGB Winds. Moshe Elitzur (Kentucky) Ž eljko Ivezi ć (Princeton) Dejan Vinkovi ć (Kentucky). Habing, Tignon & Tielens ‘94. Once the sonic point is crossed…. Radiation pressure decouples the outflow from the wind origin Subsequent outflow Radiation pressure Gas drag

derica
Download Presentation

The Structure of AGB Winds

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. The Structure of AGB Winds Moshe Elitzur (Kentucky) Željko Ivezić (Princeton) Dejan Vinković (Kentucky)

  2. Habing, Tignon & Tielens ‘94 Once the sonic point is crossed… • Radiation pressure decouples the outflow from the wind origin • Subsequent outflow • Radiation pressure • Gas drag • Gravity

  3. Radiation pressure • Gas drag • Gravity  Just math… Elitzur & Ivezic ‘01

  4. Solution of HTT ‘1st simplified model’ – negligible reddening

  5. Physical Domain <>F  V (1 + V)-0.36

  6. (HTT)

  7. Scaling Away from boundaries, wind structure fully controlled by 

  8. Scale of v set by Velocity Profile V < 1: k = 2/3 (drift) V > 1: k  0.4 (reddening)

  9. Radiation pressure: • v L1/2 • v independent of K. Young 1995: Miras, low : • v independent of L

  10. Lower – decoupling: • Higher – reddening: Drift + Reddening effect on v

  11. Data Same ndd/nH for C- and O-stars!

  12. Ivezic & Elitzur ’03 v = 18 SED Analysis • Shape  V • Flux level   Zubko & Elitzur ’00 v = 0.83 Solutions by DUSTYhttp://www.pa.uky.edu/~moshe/dusty/

  13.  + distance  L • L + v   , 22 W Hya

  14. AGB winds are generally spherical,PN are asymmetric. How come?

  15. IRC+10216 – the mother of all C-stars HCN J = 1 – 0 Dayal & Bieging ‘95

  16. IRC+10216 – K band Weigelt, G. et al. ‘02

  17. IRC+10216 – the bipolarity inside • Spherical at ~ 4,000 AU (molecules; Lindqvist et al ‘00) • Asymmetric at ~ 60 AU (K-band; Men'shchikov et al ’02) • V ~ 40 (equator) – 20 (poles) • ~ 10-5 Myr-1 3·10-4 Myr-1about 50 years ago

  18. IRC+30219 (CIT6) b v r Schmidt, G.D et al. ApJ (2002)

  19. CIT6 – Molecules Lindqvist et al ‘00

  20. CIT6 – the bipolarity outside? • Asymmetric at ~ 5,000 AU – both molecules and K-band (JET!) • The next phase of IRC+10216?

  21. What about O-rich stars? • IRC+10011 – the mother of all OH/IR stars

  22. IRC+10011 (CIT3)  = 1.24 m  = 1.65 m Vinković et al ‘03 Hofmann et al ‘01  = 2.12 m

  23. Successful fit of SED and 4 images (visibilities)

  24. IRC+10011 – the bipolarity inside • Spherical at K-band and beyond • Asymmetric at J-band; scale ~ 100 AU, ~ 100 yr (?) • V ~ 40 (equator) – 20 (poles) • ~ 1 – 2·10-5 Myr-1

  25. W43A – the Jets are Out! Imai et al ‘02

  26. Conclusions • The “standard model” works • Single variable – • Dust drift – major ingredient • 22 ~ 1 for both O- and C-rich; why? • AGB wind phase ends with jets • how prevalent? • time scales?

More Related