Geodesic
The hydrodinamical mechanism of jets’ formation and collimation in young star objects
Matematičeskaâ fizika i kompʹûternoe modelirovanie, Tome 20 (2017) no. 6, pp. 51-62 Cet article a éte moissonné depuis la source Math-Net.Ru

Voir la notice de l'article

The results of numerical hydrodynamical simulation of shock shells evolution in young star objects are presented. We have shown that during the expanding process of such shell, a slowly rotating supersonic collimated jet made of accretion disk substance forms inside the shell through the development of consequence “ejection – thorus – tornado – jet”. The mechanism of outflow’s forming and collimation is only hydrodynamical and based on the conservation law of angular momentum. It must work for all accretion-jet systems. Additional factors (such as magnetic fields) can modify such mechanism, but not eliminate it. Let's list the main conclusions: 1) The jet is formed from the substance of the circumstellar disc. It has an angular momentum co-ordinated with the symmetry axis of the system. 2) If a one-sided ejection of matter takes place, then the shock wave, caused by it, passes through a thin circumstellar disk. Then it forms a shock wave (shell) on the other side of the disk. 3) At high initial ejection velocities, there is a significant elongation of the head of the shell. This is typical for many observable young star objects. 4) The formation of the jet is due to the presence of a long-lived torus-like vortex, in which the gas rotates both along the toroidal axis and around it.
Keywords: jet outflows, young star objects, Herbig - Haro objects, numerical simulation, mechanisms of collimation. 
@article{VVGUM_2017_20_6_a4,
     author = {N. M. Kuz'min and S. S. Khrapov and V. V. Musts{\cyre}voy},
     title = {The hydrodinamical mechanism of jets{\textquoteright} formation and collimation in young star objects},
     journal = {Matemati\v{c}eska\^a fizika i kompʹ\^uternoe modelirovanie},
     pages = {51--62},
     year = {2017},
     volume = {20},
     number = {6},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/VVGUM_2017_20_6_a4/}
}
TY  - JOUR
AU  - N. M. Kuz'min
AU  - S. S. Khrapov
AU  - V. V. Mustsеvoy
TI  - The hydrodinamical mechanism of jets’ formation and collimation in young star objects
JO  - Matematičeskaâ fizika i kompʹûternoe modelirovanie
PY  - 2017
SP  - 51
EP  - 62
VL  - 20
IS  - 6
UR  - http://geodesic.mathdoc.fr/item/VVGUM_2017_20_6_a4/
LA  - ru
ID  - VVGUM_2017_20_6_a4
ER  - 
%0 Journal Article
%A N. M. Kuz'min
%A S. S. Khrapov
%A V. V. Mustsеvoy
%T The hydrodinamical mechanism of jets’ formation and collimation in young star objects
%J Matematičeskaâ fizika i kompʹûternoe modelirovanie
%D 2017
%P 51-62
%V 20
%N 6
%U http://geodesic.mathdoc.fr/item/VVGUM_2017_20_6_a4/
%G ru
%F VVGUM_2017_20_6_a4
N. M. Kuz'min; S. S. Khrapov; V. V. Mustsеvoy. The hydrodinamical mechanism of jets’ formation and collimation in young star objects. Matematičeskaâ fizika i kompʹûternoe modelirovanie, Tome 20 (2017) no. 6, pp. 51-62. http://geodesic.mathdoc.fr/item/VVGUM_2017_20_6_a4/

[1] N. M. Kuzmin, V. V. Mustsevoy, S. S. Khrapov, “The Investigation of Dispersion Properties of Small Perturbations in Jet Outflows From Young Stars”, Science Journal of Volgograd State University. Mathematics. Physics, 2002, no. 7, 76–94

[2] N. M. Kuzmin, V. V. Mustsevoy, S. S. Khrapov, “Numerical Modeling of the Evolution of Unstable Modes of Jets From Young Stellar Objects”, Astronomy Reports, 84:12 (2007), 1089–1098

[3] K. A. Levin, V. V. Mustsevoy, S. S. Khrapov, “Jets and Disks Around Young Stars”, Astronomy Reports, 76:2 (1999), 126–135

[4] P. E. Hardee, J. M. Stone, “The Stability of Radiatively Cooling Jets I. Linear Analysis”, Astrophysical Journal, 483 (1997), 121–335 | DOI

[5] B. van Leer, “Towards the Ultimate Conservative Difference Scheme V. A Second Order Sequel to Godunov’s Method”, Journal of Computational Physics, 32:1 (1979), 101–136 | DOI | MR | Zbl

[6] L. T. Little, “Interstellar Molecular Discs around Young Stars”, Quarterly Journal of the Royal Astronomical Society, 35 (1994), 11–42

[7] J. MacDonald, M. E. Bailey, “The Evolution of Flows of Stellar Mass Loss in Active Galaxies”, Monthly Notices of the Royal Astronomical Society, 197 (1981), 995–1019 | DOI

[8] R. Mundt, T. P. Ray, A. C. Raga, “Collimation of Stellar Jets – Constraints from the Observed Spatial Structure II. Observational Results”, Astronomy and Astrophysics, 252 (1991), 740–761

[9] R. Mundt, “Jets from Young Stars – Estimates of their Physical Parameters”, Canadian Journal of Physics, 64 (1986), 407–413 | DOI | MR

[10] R. Mundt, “Jets from Young Stars”, Mitteilungen der Astronomischen Gesellschaft Hamburg, 70 (1987), 100–115

[11] R. Mundt, E. W. Brugel, T. Buehrke, “Jets from Young Stars — CCD Imaging, Long-Slit Spectroscopy, and Interpretation of Existing Data”, Astrophysical Journal, 319 (1987), 275–303 | DOI

[12] R. Ouyed, R. E. Pudritz, “Numerical Simulations of Astrophysical Jets from Keplerian Disks I. Stationary Models”, Astrophysical Journal, 482 (1997), 712–732 | DOI

[13] A. C. Raga, R. Mundt, T. P. Ray, “Collimation of stellar jets — Constraints from the Observed Spatial Structure I. Data Analysis Methods”, Astronomy and Astrophysics, 252 (1991), 733–739