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In this paper, the goals and methods of deep redshift surveys are reviewed and on-going projects are discussed. The requirements on instrumentation and observations methods are very stringent and call for a dedicated approach. Among the several on-going deep surveys, we are describing the VIMOS VLT Deep Survey (VVDS) which our team is conducting. It aims to obtain spectra in the redshift range 0 <...
Deep optical and near infrared images of the NHDF with HST provide information and place constraints on models of galaxy formation and evolution. Successful theories should match these observations. The constraints go from model and cosmology independent observations such as the apparent magnitude function to heavily cosmology and model dependent constraints such as the star formation history. All...
Limiting the number of model-dependent assumptions to a minimum, we discuss the detectability of the sources responsible for reionization with existing and planned telescopes. We conclude that if reionization sources are UV-efficient, minimum luminosity sources, then it may be difficult to detect them before the advent of the James Webb Space Telescope (JWST). The best approach before the launch of...
The Lenses Structure & Dynamics (LSD) Survey aims at studying the internal structure of luminous and dark matter - as well as their evolution - of field earlytype (E/SO) galaxies to z ∼ 1. In particular, E/S0 lens galaxies are studied by combining gravitational lensing, photometric and kinematic data obtained with ground-based (VLA/Keck/VLT) and space-based telescopes (HST). Here, we report on...
We present different methods used to identify high redshift (z > 5) objects in the high-magnification regions of lensing galaxy clusters, taking advantage of very well constrained lensing models. The research procedures are explained and discussed. The detection of emission lines in the optical/NIR spectra, such as Lyman-alpha, allows us to determine the redshift of these sources. Thanks to the...
With around 23000 QSOs, the recently completed 2dF QSO Redshift Survey (2QZ) is currently the largest individual QSO survey. Here we present a measurement of the QSO power spectrum, and investigate new constraints on Ω and Λ from redshift-space distortions in the power spectrum, and weak lensing of 2QZ QSOs by foreground galaxy groups.
We present the results of detailed studies of the astrophysical conditions in z ∼ 3 Lyman Break Galaxies (LBGs), placing particular emphasis on what is learned from LBG rest frame UV spectra. By drawing from our database of ∼ 1000 spectra, and constructing higher S/N composite spectra from galaxies grouped according to various parameters, we can show how the rest-frame UV spectroscopic properties...
With the large homogeneous dataset and the accurate photometric redshifts (Δz/(z+1)≈0.03) of the FORS Deep Field (FDF) we are able to study the evolution of the luminosity function in various bands from low (〈z〉=0.3) to high redshift (〈z〉=4.5). We find a strong brightening of M* and decrease of φ* with redshift in the rest-frame UV. We also find an increase of the star formation rate (SFR) between...
We use the clustering results obtained by Madgwick et al. (2003) for a sample of 96,791 2dF galaxies with redshift 0.01<z<0.15 to study the distribution of late-type and early-type galaxies within dark matter haloes of different mass. The adopted method relies on the connection between the distribution of sources within haloes and their clustering properties by focusing on the issue of the halo...
Understanding when galaxies form via star formation histories and stellar mass assembly rates is becoming known with some certainty, yet the connection between high redshift and low redshift galaxy populations is not yet clear. By identifying and studying individual massive galaxies at high-redshifts, z > 1.5, we can uncover the physical effects that drove galaxy formation. Using the structures...
The Canada-France Deep Fields (CFDF) and the VIRMOS Deep Imaging Survey (VDIS) are deep, wide angle, multi-colour imaging surveys. The CFDF covers ∼0.65 deg2 in U BV I and reaches a limiting magnitude of UAB(3σ, 3″)∼27.5. The VDIS deep field covers∼1.2 deg2 in BV RI and reaches a limiting magnitude of BAB(3σ, 3″) ∼ 26.5. With these data, we are able to identify some of the largest samples of photometrically...
Understanding the clustering of galaxies has long been a goal of modern observational cosmology. Redshift surveys have been used to measure the correlation length as a function of luminosity and color. However, when subdividing the catalogs into multiple subsets, the errors increase rapidly. Utilizing our photometric redshift technique a volume limited sample (0.1<z<0.3) containing more than...
In this work we present combined optical and X-ray cluster detection methods in an area near the North Galactic Pole area, previously covered by the SDSS and 2dF optical surveys. The same area has been covered by shallow (∼ 1.8 deg2) XMM-Newton observations. The optical cluster detection procedure is based on merging two independent selection methods - a smoothing+percolation technique, and a Matched...
We investigate photometric and clustering properties of galaxies at z=3.5–5.2 based on large samples of 2,600 Lyman Break Galaxies (LBGs) and Lyman α Emitters (LAEs) detected in deep (i′∼27) and wide-field (1,200 arcmin2) images taken in the Subaru Deep Field (SDF) and the Subaru/XMM Deep Field (SXDF). We find in the luminosity functions of LBGs that the number density of bright galaxies (M1700<−22;...
We have discovered extended Lyman-α emission around a z=4.5 QSO in a deep long-slit spectrum with Keck/LRIS at moderate spectral resolution (R≈ 1000). The line emission extends 5 arcsec beyond the continuum of the QSO and is spatially asymmetric. This extended line emission has a spectral extent of 1000km/s, much narrower in velocity spread than the broad Lyman-α from the QSO itself and slightly offset...
We present a quantitative method of classification of the multi-wavelength morphology of galaxies, elaborated from the nearby galaxies and usable to high redshift objects. We use the morphological parameters of concentration of light at the galaxy center and 180°-rotational asymmetry, computed in several wavelengths, from ultraviolet (UV) to R band. The variation of these indices with λ reflects the...
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