A simple model for galaxy formation
Numerical experiments concerning the dynamics of a distribution of interacting gas clouds in a proto-galactic potential well are analyzed. Dissipation of energy by means of inelastic cloud collisions produce, after a few free fall times a strong flattening and a large ratio of rotational vs. total k...
Guardado en:
| Autores principales: | , , , |
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| Formato: | Articulo Comunicacion |
| Lenguaje: | Español |
| Publicado: |
1988
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| Materias: | |
| Acceso en línea: | http://sedici.unlp.edu.ar/handle/10915/142268 |
| Aporte de: |
| Sumario: | Numerical experiments concerning the dynamics of a distribution of interacting gas clouds in a proto-galactic potential well are analyzed. Dissipation of energy by means of inelastic cloud collisions produce, after a few free fall times a strong flattening and a large ratio of rotational vs. total kinetic energy for the clouds with several collisions. The adimensional spin parameter λ= J |E|^(1/2) G⁻¹ M^(-5/2) reaches high values (A > 0.25) for this highly dissipative component, remaining constant at the initial value (λ≃0.07) for those clouds that never collided, as expected from tidal torquing theory of angular momentum origin in proto-galaxles. After the collapse, the resulting systems live in a "long“ stationary State, where the collisions gradually increase the number of "star clusters", constituted by gas clouds after a threshold condition of collision. Gas dynamical effects involving energy dissipation and relaxation processes play fundamental roles in the galaxy formal ion model depicted here. We conclude from our experiments that accretion from a gaseous medium surrounding a galactic potential well can account for may desirable properties of a simple model of disk galaxy formation, based on the standard model (Eggen et al, 1962). |
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