ﻻ يوجد ملخص باللغة العربية
We present our analysis of UV attenuation by internal dust of a large sample (N=906 galaxies) of Lyman Break Galaxies (LBGs). Using spectral energy distributions (SEDs) from the PEGASE galaxy spectral evolution model we apply dust attenuation corrections to the G-R colors using the Witt & Gordon (2000) models for radiative transfer in dusty galactic environments to arrive at the UV attenuation factors. We show that the dust in the LBGs exhibit SMC-like characteristics rather than MW-like, and that the dust geometry in these systems is most likely to be represented by a clumpy shell configuration. We show that the attenuation factor exhibits a pronounced dependence on the luminosity of the LBG, $a_{1600}propto (L/L_sun)^alpha$, where $0.5leqalphaleq1.5$. The exponent $alpha$ depends on the initial parameters of the stellar population chosen to model the galaxies and the dust properties. We find that the luminosity weighted average attenuation factor is likely to be in the range from $5.7-18.5$, which is consistent with the upper limits to the star formation rate at $2<z<4$ set by the FIR background. This implies that the current UV/optical surveys do detect the bulk of the star formation during the epoch $2<z<4$, but require substantial correction for internal dust attenuation.
We explore from a statistical point of view the far-infrared (far-IR) and sub-millimeter (sub-mm) properties of a large sample of LBGs (22,000) at z~3 in the COSMOS field. The large number of galaxies allows us to split it in several bins as a functi
Using GALFORM, a semi-analytical model of galaxy formation in the Lambda cold dark matter cosmology, we study the rest-frame ultraviolet (UV) colours of Lyman-break galaxies (LBGs) in the redshift range 2.5 < z < 10. As the impact of dust on UV lumin
We use hydrodynamic simulations to predict correlations between Lya forest absorption and galaxies at redshift z~3. The probability distribution function (PDF) of Lya flux decrements shifts systematically towards higher values in the vicinity of gala
We make a detailed investigation of the properties of Lyman-break galaxies (LBGs) in the LambdaCDM model. We present predictions for two published variants of the GALFORM semi-analytical model: the Baugh et al. (2005) model, which has star formation
Ultraviolet (UV) galaxies have been selected from GALEX. The presence of a FUV-dropout in their spectral energy distributions proved to be a very complete (83.3%) but not very efficient (21.4%) tool for identifying Lyman Break Galaxies (LBGs) at z~1.