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In this Thesis we investigate the evolutionary histories of faint field galaxies using extremely deep optical and near-infrared photometry. Our work is centred on a 50 arcmin(^2) region at high galactic latitude which we call "The William Herschel Deep Field" (WHDF). In this work we describe three new near-infrared surveys of this field. In considering both this infrared data and the existing optical data, our broad aims are to increase our understanding of both the growth of galaxy clustering in the Universe and also to determine the star-formation histories of the field galaxy population. We consider our observations primarily in the context of luminosity evolution models in low density universes, but alternative scenarios are considered. Near-infrared galaxy counts derived from our catalogues are consistent with the predictions of our models, without the need for a steep faint-end slope for the galaxy luminosity function. We find that optical-infrared colour distributions of infrared-selected galaxies in the WHDF are deficient in red, early-type galaxies. This is consistent with the predictions of evolutionary models in which these systems have a small amount of on-going star-formation. We measure the amplitude of galaxy clustering in the WHDF for galaxies selected in optical and near-infrared bandpasses using the projected two-point correlation function. By comparing our measured clustering amplitudes with the predictions of our models we find that in all bandpasses the growth of galaxy clustering is approximately fixed in proper co-ordinates, again assuming a low-density Universe. Finally, an analysis of errors on the correlation function measurements suggest that discrepancies between our work and those of other authors may be explained by an underestimation of statistical errors.

We present two self-consistent non-parametric models of the local cosmic velocity field based on the density distribution in the PSCz redshift survey of IRAS galaxies. Two independent methods have been applied, both based on the assumptions of gravitational instability and linear biasing. They give remarkably similar results, with no evidence of systematic differences and an r.m.s discrepancy of only ~ 70 kms(^-1) in each Cartesian velocity component. These uncertainties are consistent with a detailed independent error analysis carried out on mock PSCz catalogues constructed from TV-body simulations. The denser sampling provided by the PSCz survey compared to previous IRAS galaxy surveys allows us to reconstruct the velocity field out to larger distances. The most striking feature of the model velocity field is a coherent large-scale streaming motion along a basehne connecting Perseus-Pisces, the Local Supercluster, the Great Attractor, and the Shapley Concentration. We find no evidence for back-infall onto the Great Attractor. Instead, material behind and around the Great Attractor is inferred to be streaming towards the Shapley Concentration, aided by the expansion of two large neighbouring un- derdense regions. The PSCi model velocities compare well with those predicted from the 1.2-Jy redshift survey of IRAS galaxies and, perhaps surprisingly, with those predicted from the distribution of Abell/ACO clusters, out to 140 h(^-1)Mpc. Comparison of the real-space density fields (or, alternatively, the peculiar velocity fields) inferred from the PSCz and cluster catalogues gives a relative (linear) bias parameter between clusters and IRAS galaxies of b(_c) = 4.4 ± 0.6. In addition, we compare the cumulative bulk flows predicted from the PSCz gravity field with those measured from the MarkIII and SFI catalogues of peculiar velocities. A conservative estimate of β = Ω(_0)(^0.6)/b, where b is the bias parameter for IRAS galaxies, gives β= 0.76 ± 0.13 (1-σ), in agreement with other recent determinations. Finally, we perform a detailed comparison of the IRAS PSCz and 1.2-Jy spherical harmonic coefficients of the density and velocity fields in redshift space. Both the monopole terms of the density and velocity fields predicted from the surveys show some inconsistencies. The mismatch in the velocity monopole terms is resolved by masking the 1.2-Jy survey with the PSCz mask and using the galaxies within the PSCz survey for fluxes larger than 1.2 Jy. Davis, Nusser and Willick (1996) have found a discrepancy between the IRAS 1.2-Jy survey gravity field and the MarkIII peculiar velocity field. We conclude that the use of the deeper IRAS PSCz catalogue cannot alone resolve this mismatch.

Cette thèse porte sur l'étude des propriétés et l'évolution de regroupement de galaxies pour les galaxies de la gamme de 2<z<5 de VUDS Sondage, qui est la plus grande enquête de galaxie spectroscopique à z>2. Je ai pu mesurer la distribution spatiale d'une population générale de galaxie à redshift z~3 pour la première fois avec une grande précision. Je ai quantifié le regroupement de galaxie en estimation et la modélisation de la fonction de corrélation projetée (espace réel) à deux points, pour une population générale de 3022 galaxies. Je ai prolongé les mesures de regroupement à la luminosité et des sous-échantillons de masse sélectionné stellaires. Mes résultats montrent que la force de regroupement de la population générale de la galaxie ne change pas de redshift z~3,5 à z~2,5, mais dans les deux redshift va plus lumineux et des galaxies plus massives sont plus regroupées que les moins lumineux (massives). En utilisant la distribution d'occupation de halo (HOD) formalisme je mesuré une masse moyenne de halo hôte au redshift z~3 significativement plus faible que les masses halo moyens observés à faible redshift. Je ai conclu que la population de formation d'étoiles observé des galaxies à z~3 aurait évolué dans le massif et lumineux la population de galaxies au z=0. Aussi, je interpréter les mesures de regroupement en termes de biais de galaxies à grande échelle linéaire. Je trouve que ce est nettement plus élevé que le biais des galaxies redshift intermédiaire et faible. Enfin, je ai calculé le ratio-stellaire Halo masse (SHMR) et l'efficacité intégrée de formation d'étoiles (ISFE) pour étudier l'efficacité de la formation des étoiles et l'assemblage masse stellaire. / This thesis focuses on the study of the properties and evolution of galaxy clustering for galaxies in the redshift range 2<z<5 from the VIMOS Ultra Deep Survey (VUDS), which is the largest spectroscopic galaxy survey at z>2. I was able to measure the spatial distribution of a general galaxy population at redshift z~3 for the first time with a high accuracy. I quantified the galaxy clustering by estimating and modelling the projected (real-space) two-point correlation function, for a general population of 3022 galaxies. I extended the clustering measurements to the luminosity and stellar mass-selected sub-samples. My results show that the clustering strength of the general galaxy population does not change significantly from redshift z~3.5 to z~2.5, but in both redshift ranges more luminous and more massive galaxies are more clustered than less luminous (massive) ones. Using the halo occupation distribution (HOD) formalism I measured an average host halo mass at redshift z~3 significantly lower than the observed average halo masses at low redshift. I concluded that the observed star-forming population of galaxies at z~3 might have evolved into the massive and bright (Mr<-21.5) galaxy population at redshift z=0. Also, I interpret clustering measurements in terms of a linear large-scale galaxy bias. I find it to be significantly higher than the bias of intermediate and low redshift galaxies. Finally, I computed the stellar-to-halo mass ratio (SHMR) and the integrated star formation efficiency (ISFE) to study the efficiency of star formation and stellar mass assembly. I find that the integrated star formation efficiency is quite high at ~16% for the average galaxies at z~3.

We present a precision study of large-scale structure from large galaxy redshift surveys. We focus on two main subjects of large-scale structure: precisioncosmology with baryon acoustic oscillations from large galaxy surveys and the evolution of galaxy clustering for passively flowing galaxies.The baryon acoustic oscillations in galaxy redshift surveys can serve as an efficient standard ruler to measure the cosmological distance scale, i.e., theangular diameter distances and Hubble parameters, as a function of redshift, and therefore dark energy parameters. We use a Fisher matrix formalism to show that such a standard ruler tests can constrain the angular diameter distances and Hubble parameters to a precision of a few percent, thereby providing robust measurements of present-day dark energy density and its time-dependence.We use N-body simulations to investigate possible systematic errors in the recovery of the cosmological distance scale from galaxy redshift surveys. We show that the baryon signature on linear and quasi-linear scales is robust against nonlinear growth, redshift distortions, and halo (or galaxy) bias, albeit partial obscuration of the signature occurs due to nonlinear growth and redshift distortions.We present the improved Fisher matrix formalism which incorporates the Lagrangian displacement field to describe the nonlinear effects on baryon signature as a function of time and scale. We present a physically motivated, reduced 2-dimensional fitting formula for the full Fisher matrix formalism. We show that distance precision from the revised formalism is in excellent agreement with distance precision from N-body simulations.Finally, we present a numerical study of the evolution of galaxy clustering when galaxies flow passively from high redshift to low redshift, that is, without merging or new formations. We show that passive flow evolution induces interesting characteristics in the galaxy distribution at low redshift: we find an asymptotic convergence in galaxy clustering and halo occupation distribution regardless of the initial distribution of galaxies.

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