Magnification cross-sections of gravitational lensing by galaxies in general FLRW cosmologies
| dc.creator | Zhu, Zong-Hong | |
| dc.date | 2000-07-29 | |
| dc.date.accessioned | 2026-07-07T10:47:16Z | |
| dc.date.available | 2026-07-07T10:47:16Z | |
| dc.description | For a wide variety of cosmological models characterized by the cosmic mass density $Ω_M$ and the normalized cosmological constant $Ω_Λ$, we derive an analytic expression for the estimate of magnification cross-sections by an ensemble of isothermal spheres as models of galactic mass distributions. This provides a simple approach to demonstrate how the lensing probability by galaxies depends on the cosmological parameters. An immediate consequence is that, while a non-zero cosmological constant indeed leads to a significant increase of the lensing probability as it has been shown in the literature, only a small fraction of sky to $z\sim 3$ can be moderately ($μ\sim 1.3$) lensed by galaxies even in a $Λ$-dominated flat universe. Therefore, whether or not there is a nonzero cosmological constant, it is unlikely that the overall quasar counts have been seriously contaminated by the presence of galactic lenses. | |
| dc.description | 5 pages, two figures, aa.sty Latex | |
| dc.identifier | https://arxiv.org/abs/astro-ph/0007457 | |
| dc.identifier | http://arxiv.org/abs/astro-ph/0007457 | |
| dc.identifier | Astron.Astrophys.338:777,1998 | |
| dc.identifier.uri | http://salesiana.dossiersoluciones.com/handle/123456789/183476 | |
| dc.subject | Astrophysics | |
| dc.title | Magnification cross-sections of gravitational lensing by galaxies in general FLRW cosmologies | |
| dc.type | text |