This is the first paper of a series that will present data and scientific results from the WINGS project, a wide- field, multiwavelength imaging and spectroscopic survey of galaxies in 77 nearby clusters. The sample was extracted from the ROSAT catalogs of X- Ray emitting clusters, with constraints on the redshift (0.04 < z < 0.07) and distance from the galactic plane (vertical bar b vertical bar >= 20 deg). The global goal of the WINGS project is the systematic study of the local cosmic variance of the cluster population and of the properties of cluster galaxies as a function of cluster properties and local environment. This data collection will allow the definition of a local, '' zero- point '' reference against which to gauge the cosmic evolution when compared to more distant clusters. The core of the project consists of wide- field optical imaging of the selected clusters in the B and V bands. We have also completed a multifiber, medium- resolution spectroscopic survey for 51 of the clusters in the master sample. The imaging and spectroscopy data were collected using, respectively, the WFC@ INT and WYFFOS@ WHT in the northern hemisphere, and the WFI@ MPG and 2dF@ AAT in the southern hemisphere. In addition, a NIR (J, K) survey of similar to 50 clusters and an H-a + U survey of some 10 clusters are presently ongoing with the WFCAM@ UKIRT and WFC@ INT, respectively, while a very- wide- field optical survey has also been programmed with OmegaCam@ VST. In this paper we briefly outline the global objectives and the main characteristics of the WINGS project. Moreover, the observing strategy and the data reduction of the optical imaging survey (WINGS-OPT) are presented. We have achieved a photometric accuracy of similar to 0.025 mag, reaching completeness to V similar to 23.5. Field size and resolution (FWHM) span the absolute intervals (1.6 - 2.7) Mpc and (0.7 - 1.7) kpc, respectively, depending on the redshift and on the seeing. This allows the planned studies to obtain a valuable description of the local properties of clusters and galaxies in clusters.

We describe preliminary results from an ultra-sensitive, spectroscopic emission-line survey and illustrate the challenges inherent in identifying high-redshift Ly alpha emitters. Our multi-slit windows technique complements other types of emission-line surveys. Narrowband imagine surveys cover large areas of sky but only detect much brighter objects. Longslit spectra taken along cluster caustics yield intrinsically fainter lensed Ly alpha emitters but probe small volumes of space. We have observed the COSMOS deep field and a field at 15 h +00. To a line flux of a few similar to x 10(-18) ergs s(-1) cm(-2), we found 150 emission-line sources (with no detectable continuum) among 4 masks. These candidates are being re-observed with broad spectral coverage to determine the line identity, To date, the interloper to Ly alpha ratio is about 8:1. The sky positions of the Lya candidates generally do not coincide with those of foreground objects in ultra-deep r band or i' images consistent with the presence of a strong Lyman break. (c) 2005 Published by Elsevier B.V.

The Terrestrial Planet Finder Coronagraph (TPF-C) is a deep space mission designed to detect and characterize Earth-like planets around nearby stars. TPF-C will be able to search for signs of life on these planets. TPF-C will use spectroscopy to measure basic properties including the presence of water or oxygen in the atmosphere, powerful signatures in the search for habitable worlds. This capability to characterize planets is what allows TPF-C to transcend other astronomy projects and become an historical endeavor on a par with the discovery voyages of the great navigators.

Black hole ( BH) masses predicted from the M-center dot-sigma relationship conflict with predictions from the M-center dot-L relationship for high-luminosity galaxies, such as brightest cluster galaxies ( BCGs). The M-center dot-L relationship predicts that some BCGs may harbor BHs with M-center dot approaching 10(10) M-circle dot, while the M-center dot-sigma relationship always predicts M-center dot < 3 x 10(9) M-circle dot. We argue that the M-center dot-L relationship is a plausible description for galaxies of high luminosity. If the cores in central stellar density are formed by binary BHs, the inner core cusp radius, r(gamma), may be an independent witness of M-center dot. Using central structural parameters derived from a large sample of early-type galaxies observed by HST, we argue that L is superior to sigma as an indicator of r(gamma). Further, the r(gamma)-M-center dot relationship for 11 core galaxies with measured M-center dot appears to be consistent with the M-center dot-L relationship for BCGs. BCGs have large cores appropriate for their large luminosities that may be difficult to generate with the more modest BH masses inferred from the M-center dot-sigma relationship. M-center dot similar to M would be expected for BCGs, if they were formed in dissipationless mergers, which should preserve the ratio of BH to stellar mass, M. This scenario appears to be consistent with the slow increase in sigma with L and the more rapid increase in effective radii with L seen in BCGs as compared to less luminous galaxies. If BCGs have large BHs commensurate with their luminosities, then the local BH mass function for M-center dot > 3 x 10(9) M-circle dot would be nearly an order of magnitude richer than that inferred from the M-center dot-sigma relationship. The volume density of the most luminous QSOs may favor the M-center dot-L relationship.

Aims. We search for and characterize substructures in the projected distribution of galaxies observed in the wide field CCD images of the 77 nearby clusters of the WIde-field Nearby Galaxy-cluster Survey ( WINGS). This sample is complete in X-ray flux in the redshift range 0.04 < z < 0.07.

Context. The WIde-field Nearby Galaxy-cluster Survey (wings) is a project aiming at the study of the galaxy populations in clusters in the local universe (0.04 < z < 0.07) and the influence of environment on the physical properties of galaxies. This survey provides a high quality set of spectroscopic data for similar to 6000 galaxies in 48 clusters. The study of such a large amount of objects requires automatic tools capable of extracting as much information as possible from the data.

We combine several HST investigations on the central structure of early-type galaxies to generate a large sample of surface photometry. The studies selected were those that used the "Nuker law'' to characterize the inner light distributions of the galaxies. The sample comprises WFPC1 and WFPC2 V-band observations published earlier by our group, R-band WFPC2 photometry of Rest et al., NICMOS H-band photometry by Ravindranath et al. and Quillen et al., and the brightest cluster galaxy WFPC2 I-band photometry of Laine et al. The distribution of the logarithmic slopes of the central brightness profiles strongly affirms that the central structure of elliptical galaxies with MV < - 19 is bimodal, based on both parametric and nonparametric analysis. At the HSTresolution limit, most galaxies are either power-law systems, which have steep cusps in surface brightness, or core systems, which have shallow cusps interior to a steeper envelope brightness distribution. A rapid transition between the two forms occurs over the luminosity range - 22 < M-V < - 20, with cores dominating at the highest luminosities and power laws at the lowest. There are a few "intermediate'' systems that have both cusp slopes and total luminosities that fall within the core/power-law transition, but they are rare and do not fill in the overall bimodal distribution.

The largest galaxies, and in particular central galaxies in clusters, offer unique insight into understanding the mechanism for the growth of nuclear black holes. We present Hubble Space Telescope kinematics for NGC 1399, the central galaxy in Fornax. We find the best-fit model contains a black hole of (5.1 +/- 0: 7) x 10(8) M-circle dot (at a distance of 21.1 Mpc), a factor of over 2 below the correlation of black hole mass and velocity dispersion. We also find a dramatic signature for central tangential anisotropy. The velocity profiles on adjacent sides 0.5 '' away from the nucleus show strong bimodality, and the central spectrum shows a large drop in the dispersion. Both of these observations point to an orbital distribution that is tangentially biased. The best-fit orbital model suggests a ratio of the tangential to radial internal velocity dispersions of 3. This ratio is the largest seen in any galaxy to date and will provide an important measure for the mode by which the central black hole has grown.

We present stellar population parameters of 12 elliptical and S0 galaxies in the Coma cluster around and including the cD galaxy NGC 4874, based on spectra obtained using the Low Resolution Imaging Spectrograph on the Keck II Telescope. Our data are among the most precise and accurate absorption-line strengths yet obtained for cluster galaxies, allowing us to examine in detail the zero-point and scatter in the stellar population properties of Coma cluster early-type galaxies (ETGs). Recent observations of red sequence galaxies in the high-redshift Universe and generic hierarchical galaxy formation models lead to the following expectations for the stellar populations of local ETGs. (1) In all environments, bigger ETGs should have older stellar populations than smaller ETGs ('downsizing'); (2) ETGs at fixed stellar mass form stars earlier and thus should have older stellar population ages in the highest density environments than those in lower density environments and (3) the most massive ETGs in the densest environments should have a small spread in stellar population ages. We find the following surprising results using our sample. (1) Our ETGs have single-stellar-population-equivalent (SSP-equivalent) ages of on average 5-8 Gyr with the models used here, with the oldest galaxies having SSP-equivalent ages of less than or similar to 10-Gyr old. This average age is identical to the mean age of field ETGs. (2) The ETGs in our sample span a large range in velocity dispersion (mass) but are consistent with being drawn from a population with a single age. Specifically, 10 of the 12 ETGs in our sample are consistent within their formal errors of having the same SSP-equivalent age, 5.2 +/- 0.2 Gyr, over a factor of more than 750 in mass. We therefore find no evidence for downsizing of the stellar populations of ETGs in the core of the Coma cluster. We confirm the lack of a trend of SSP-equivalent age with mass in the core of the Coma cluster from all other samples of Coma cluster ETG absorption-line strengths available in the literature, but we do find from the largest samples that the dispersion in age increases with decreasing mass. These conclusions stand in stark contrast to the expectations from observations of high-redshift red sequence galaxies and model predictions. We suggest that Coma cluster ETGs may have formed the majority of their mass at high redshifts but suffered small but detectable star formation events at z approximate to 0.1-0.3. In this case, previous detections of 'downsizing' from stellar populations of local ETGs may not reflect the same downsizing seen in look-back studies of RSGs, as the young ages of the local ETGs represent only a small fraction of their total masses.

By exploting the data of three large surveys (WINGS, NFPS, and SDSS), we analyze the fundamental plane (FP) of early-type galaxies (ETGs) in 59 nearby clusters (0.04 < z < 0.07). We show that the variances of the FP coefficients for our clusters are just marginally consistent with the hypothesis of universality of the FP. We found they are influenced by the distribution of photometric/kinematic properties of galaxies in the particular sample under analysis, suggesting that the FP is actually a bent surface. We also find a strong correlation between the local density and the FP coefficients, while they appear to be poorly correlated with the global properties of clusters. The relation between luminosity and mass of our galaxies, computed by assuming Sersic luminosity profiles, indicates that, for a given mass, the greater the light concentration, the higher the luminosity, while, for a given luminosity, the lower the light concentration, the greater the mass. Moreover, the M/L versus mass relation (again with Sersic profile fitting) turns out to be steeper and broader than that obtained for the Coma Cluster sample with de Vaucouleurs profile fitting. This broadness, together with the FP bending, might reconcile the FP phenomenology with the expectations from the Lambda CDM cosmology. We conclude that the claimed universality of the FP of ETGs is still far from being proved and that systematic biases might affect the studies of luminosity evolution of ETGs, since data sets at different redshifts and with different distributions of the photometric/kinematic galaxy properties are compared each other.