The luminosity-redshift relation in brane-worlds: II. Confrontation with experimental data

The luminosity distance – redshift relation for a wide class of generalized Randall-Sundrum type II brane-world models with Weyl fluid is compared to the presently available supernova data. We find that there is a class of spacially flat models with different amounts of matter Ωρ and Weyl fluid Ωd, which have a very similar fitting quality. The best-fit models are equally likely and can be regarded as extensions of the ΛCDM model, which is also included. We examine three models with different evolutionary history of the Weyl fluid, characterized by a parameter α = 0, 2 and 3. The first model describes a brane which had radiated energy into the bulk some time ago, but in recent times this energy exchange has ceased and only a dark radiation (α = 0) is left. In the other two models the Weyl-fluid describes a radiating brane throughout the cosmological evolution, up to our days. We find that the throughout of the fitting surface extends over a wider Ωd-range with increasing α, but the linear correlation of Ωd and Ωρ holds all over the examined Ωd range. PACS codes: 11.25-w, 98.62.Py, 98.80.Es