On arcs and [Omega]
The gravitational lens effect of galaxy clusters can produce large arcs from source galaxies in their background. Typical source redshifts of ~ 1 require clusters at z ~ 0.3 for arcs to form efficiently. Given the cluster abundance at the present epoch, the fewer clusters exist at z ~ 0.3 the higher...
Gespeichert in:
| 1. Verfasser: | |
|---|---|
| Dokumenttyp: | Article (Journal) Kapitel/Artikel |
| Sprache: | Englisch |
| Veröffentlicht: |
24 Sep 1997
|
| In: |
Arxiv
|
| Online-Zugang: | Verlag, kostenfrei, Volltext: http://arxiv.org/abs/astro-ph/9709229
|
| Verfasserangaben: | M. Bartelmann, A. Huss, J.M. Colberg, A. Jenkins, F.R. Pearce |
| Zusammenfassung: | The gravitational lens effect of galaxy clusters can produce large arcs from source galaxies in their background. Typical source redshifts of ~ 1 require clusters at z ~ 0.3 for arcs to form efficiently. Given the cluster abundance at the present epoch, the fewer clusters exist at z ~ 0.3 the higher Omega_0 is, because the formation epoch of galaxy clusters strongly depends on Omega_0. In addition, at fixed Omega_0, clusters are less concentrated, and hence less efficient lenses, when the cosmological constant is positive, Omega_Lambda > 0. Numerical cluster simulations show that the expected number of arcs on the sky is indeed a sensitive function of Omega_0 and Omega_Lambda. The numerical results are compatible with the statistics of observed arcs only in a universe with low matter density, Omega_0 ~ 0.3, and zero cosmological constant. Other models fail by one or two orders of magnitude, rendering arc statistics a sensitive probe for cosmological parameters. |
|---|---|
| Beschreibung: | Im Titel ist Omega als griechischer Buchstabe dargestellt Gesehen am 28.09.2017 |
| Beschreibung: | Online Resource |