Density Profiles of Dark Halos from their Mass Accretion Histories
Fuente:
Redalyc
Gespeichert in:
| 1. Verfasser: | |
|---|---|
| Format: | Artículo científico |
| Sprache: | en |
| Veröffentlicht: |
Universidad Nacional Autónoma de México
2003
|
| Schlagworte: | |
| Online-Zugang: | |
| Tags: |
Tag hinzufügen
Keine Tags, Fügen Sie den ersten Tag hinzu!
|
| _version_ | 1876472259173941248 |
|---|---|
| author | M. A. Alvarez |
| author_facet | M. A. Alvarez |
| contents | Density Profiles of Dark Halos from their Mass Accretion Histories M. A. Alvarez K. Ahn P. R. Shapiro Física, Astronomía y Matemáticas large Dark Matter Cosmology: Theory Galaxies: Formation Scale Structure of Universe We use the universal mass accretion history recently reported for simulations of halo formation in the cold dark matter model (CDM) to analyze the formation and growth of a single halo. We derive the time-dependent density profile three diferent ways, based upon three approximations of successively greater realism: equilibrium, radial orbits, and a uid approximation. For the equilibrium model, the density profle is well-fit by either an NFW or Moore profile over a limited range of radii and scale factors. For the radial orbit model, we find profiles which are generally steeper than the NFW profile, with an inner logarithmic slope approaching -2, consistent with a purely radial collisionless system. In the uid approximation, we find good agreement with the NFW and Moore profiles for radii resolved by N-body simulations (r/r200 > 0.01), and an evolution of concentration parameter nearly identical to that found in N-body simulations. The evolving structure of cosmological halos is therefore best understood as the efect of a time-varying rate of mass infall on a smoothly distributed, isotropic, collisionless fuid. 2003 artículo científico 0185-1101 https://www.redalyc.org/articulo.oa?id=57101803 en http://www.redalyc.org/revista.oa?id=571 Revista Mexicana de Astronomía y Astrofísica application/pdf Universidad Nacional Autónoma de México Revista Mexicana de Astronomía y Astrofísica (México) Vol.18 |
| format | Artículo científico |
| id | redalyc_57101803 |
| institution | Redalyc |
| language | en |
| publishDate | 2003 |
| publisher | Universidad Nacional Autónoma de México |
| spellingShingle | Density Profiles of Dark Halos from their Mass Accretion Histories M. A. Alvarez Física, Astronomía y Matemáticas large Dark Matter Cosmology: Theory Galaxies: Formation Scale Structure of Universe Density Profiles of Dark Halos from their Mass Accretion Histories M. A. Alvarez K. Ahn P. R. Shapiro Física, Astronomía y Matemáticas large Dark Matter Cosmology: Theory Galaxies: Formation Scale Structure of Universe We use the universal mass accretion history recently reported for simulations of halo formation in the cold dark matter model (CDM) to analyze the formation and growth of a single halo. We derive the time-dependent density profile three diferent ways, based upon three approximations of successively greater realism: equilibrium, radial orbits, and a uid approximation. For the equilibrium model, the density profle is well-fit by either an NFW or Moore profile over a limited range of radii and scale factors. For the radial orbit model, we find profiles which are generally steeper than the NFW profile, with an inner logarithmic slope approaching -2, consistent with a purely radial collisionless system. In the uid approximation, we find good agreement with the NFW and Moore profiles for radii resolved by N-body simulations (r/r200 > 0.01), and an evolution of concentration parameter nearly identical to that found in N-body simulations. The evolving structure of cosmological halos is therefore best understood as the efect of a time-varying rate of mass infall on a smoothly distributed, isotropic, collisionless fuid. 2003 artículo científico 0185-1101 https://www.redalyc.org/articulo.oa?id=57101803 en http://www.redalyc.org/revista.oa?id=571 Revista Mexicana de Astronomía y Astrofísica application/pdf Universidad Nacional Autónoma de México Revista Mexicana de Astronomía y Astrofísica (México) Vol.18 |
| title | Density Profiles of Dark Halos from their Mass Accretion Histories |
| topic | Física, Astronomía y Matemáticas large Dark Matter Cosmology: Theory Galaxies: Formation Scale Structure of Universe |
| url | https://www.redalyc.org/articulo.oa?id=57101803 |