Astronomy and Astrophysics – Astrophysics
Scientific paper
2001-09-11
Astronomy and Astrophysics
Astrophysics
Astronomy & Astrophysics (in press) High resolution figures at ftp://ftp.astro.up.pt/pub/preprints/95.ps.gz
Scientific paper
10.1051/0004-6361:20011145
Motivated by recent subarcsecond resolution observations of jets from T Tauri stars, we extend the work of \citep{Safier93a, Safier93b} by computing the thermal and ionization structure of self-similar, magnetically-driven, atomic disk winds heated by ambipolar diffusion. Improvements over his work include: (1) new magnetized cold jet solutions consistent with the underlying accretion disk \citep{Ferreira97}; (2) a more accurate treatment of ionization and ion-neutral momentum exchange rates; and (3) predictions for spatially resolved forbidden line emission (maps, long-slit spectra, and line ratios), presented in a companion paper, \cite{Garcia2001b}. As in \citep{Safier93a}, we obtain jets with a temperature plateau around $10^4$ K, but ionization fractions are revised downward by a factor of 10-100. This is due to previous omission of thermal speeds in ion-neutral momentum-exchange rates and to different jet solutions. The physical origin of the hot temperature plateau is outlined. In particular we present three analytical criteria for the presence of a hot plateau, applicable to any given MHD wind solution where ambipolar diffusion and adiabatic expansion are the dominant heating and cooling terms. We finally show that, for solutions favored by observations, the jet thermal structure remains consistent with the usual approximations used for MHD jet calculations (thermalized, perfectly conducting, single hydromagnetic cold fluid calculations).
Binette Luc
Cabrit Sylvie
Ferreira Jonathan
Garcia Paulo J. V.
No associations
LandOfFree
Atomic T Tauri disk winds heated by ambipolar diffusion I- Thermal structure does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Atomic T Tauri disk winds heated by ambipolar diffusion I- Thermal structure, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Atomic T Tauri disk winds heated by ambipolar diffusion I- Thermal structure will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-710954