M. Ramella, W. Boschin, D. Fadda, M. Nonino
Abstract. We present an objective and automated procedure for detecting clusters of galaxies in imaging galaxy surveys ⋆. Our Voronoi Galaxy Cluster Finder (VGCF) uses galaxy positions and...
WINGS-SPE Spectroscopy in the WIde-field Nearby Galaxy-cluster Survey (2008)
Cava, A., Bettoni, D., Poggianti, B. M., Couch, W. J., Moles, M., Varela, J., ...
Aims. We present the results from a comprehensive spectroscopic survey of the WINGS (WIde-field Nearby Galaxy-cluster Survey) clusters, a program called WINGS-SPE. The WINGS-SPE sample consists of 48...
Substructures in WINGS clusters (2007)
Ramella, M., Biviano, A., Pisani, A., Varela, J., Bettoni, D., Couch, W. J., ...
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...
Substructures in WINGS clusters (2007)
Ramella, M., Biviano, A., Pisani, A., Varela, J., Bettoni, D., Couch, W. J., ...
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...
Substructures in WINGS clusters (2007)
Ramella, M., Biviano, A., Pisani, A., Varela, J., Bettoni, D., Couch, W. J., ...
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...
Optically-selected clusters at 0.8 < z < 1.3 in the EIS Cluster Survey (2005)
Benoist, C., Da Costa, L., Jørgensen, H. E., Olsen, L. F., Bardelli, S., Zucca, E., ...
This paper presents preliminary results of a spectroscopic survey being conducted at the VLT of fields with optically-selected cluster candidates identified in the EIS I-band survey. Here we report...
New spectroscopic confirmations of high-redshift galaxy clusters (2005)
Olsen, L. F., Zucca, E., Bardelli, S., Benoist, C., Da Costa, L., Jørgensen, H. E., ...
We present new spectroscopic data in the field of five high-redshift (z>=0.6) candidate galaxy clusters, drawn from the EIS Cluster Candidate Catalog. A total of 327 spectra were obtained using FORS1...
VGCF Detection of Galaxy Systems at Intermediate Redshift (2005)
Barrena, R., Ramella, M., Boschin, W., Nonino, M., Biviano, A., Mediavilla, E.
We continue the development of our Voronoi Galaxy Cluster Finder (VGCF) technique by applying it to galaxy catalogs obtained with B and R band observations of four high galactic latitude fields of...
K-band Properties of Well-Sampled Groups of Galaxies (2004)
Ramella, M., Boschin, W., Geller, M. J., Mahdavi, A., Rines, K.
We use a sample of 55 groups and 6 clusters of galaxies ranging in mass from 7 x 10^11 Msun to 1.5 x 10^15 Msun to examine the correlation of the Ks-band luminosity with mass discovered by Lin et al....
Internal dynamics of the radio--halo cluster A2219: a multi-wavelength analysis (2003)
Boschin, W., Girardi, M., Delgado, R. Barrena, Biviano, A., Feretti, L., Ramella, M.
We present the results of the dynamical analysis of the rich, hot, and X-ray very luminous galaxy cluster A2219, containing a powerful diffuse radio-halo. Our analysis is based on new redshift data...
The origin of X-ray emission of two distant (z>1) cluster candidate with XMM-Newton (2003)
Neumann, D. M., Arnaud, M., Benoist, C., Da Costa, L., Jørgensen, H. E., Olsen, L. F., ...
We present here a study of XMM-Newton data of two distant galaxy cluster candidates. One of these was discovered serendipitously in near infrared data, CL J0533-2411, the other one corresponds to the...
Optically-selected clusters at 0.8 < z < 1.3 in the EIS Cluster Survey (2002)
Benoist, C., Da Costa, L., Jørgensen, H. E., Olsen, L. F., Bardelli, S., Zucca, E., ...
This paper presents preliminary results of a spectroscopic survey being conducted at the VLT of fields with optically-selected cluster candidates identified in the EIS I-band survey. Here we report...
The Dynamical Status of the Cluster of Galaxies 1E0657-56 (2002)
Barrena, R., Biviano, A., Ramella, M., Falco, E. E., Seitz, S.
We present the results of a new spectroscopic and photometric survey of the hot X-ray cluster 1E0657-56, at z=0.296. We determine the presence of a low velocity dispersion subcluster, which is offset...
Optically-selected clusters at 0.8 < z < 1.3 in the EIS Cluster Survey (2002)
Benoist, C., Da Costa, L., Jørgensen, H. E., Olsen, L. F., Bardelli, S., Zucca, E., ...
This paper presents preliminary results of a spectroscopic survey being conducted at the VLT of fields with optically-selected cluster candidates identified in the EIS I-band survey. Here we report...
Optically-selected clusters at 0.8 < z < 1.3 in the EIS Cluster Survey (2002)
Benoist, C., Da Costa, L., Jørgensen, H. E., Olsen, L. F., Bardelli, S., Zucca, E., ...
This paper presents preliminary results of a spectroscopic survey being conducted at the VLT of fields with optically-selected cluster candidates identified in the EIS I-band survey. Here we report...
On the Nature of the EIS Candidate Clusters: Confirmation of z (2001)
Olsen, L. F., Benoist, C., Da Costa, L., Scodeggio, M., Jorgensen, H. E., Arnouts, S., ...
We use public V-band imaging data from the wide-angle surveys conducted by the ESO Imaging Survey project (EIS) to further investigate the nature of the EIS galaxy cluster candidates. These were...
Finding Galaxy Clusters using Voronoi Tessellations (2001)
Ramella, M., Boschin, W., Fadda, D., Nonino, M.
We present an objective and automated procedure for detecting clusters of galaxies in imaging galaxy surveys. Our Voronoi Galaxy Cluster Finder (VGCF) uses galaxy positions and magnitudes to find...
Optical/Infrared Survey of Galaxy Clusters (2000)
Da Costa, Luiz, Arnouts, S., Bardelli, S., Benoist, C., Biviano, A., Borgani, S., ...
In this contribution the ongoing effort to build a statistical sample of clusters of galaxies over a wide range of redshifts to study the evolution of clusters and member galaxies is reviewed. The...
Spectroscopic confirmation of clusters from the ESO imaging survey (2000)
Ramella, M., Biviano, A., Boschin, W., Bardelli, S., Scodeggio, M., Borgani, S., ...
We measure redshifts for 67 galaxies in the field of six cluster candidates from the ESO Imaging Survey (EIS). The cluster candidates are selected in the EIS patches C and D among those with...
The RASSCALS: An X-ray and Optical Study of 260 Galaxy Groups (1999)
Mahdavi, A., Boehringer, H., Geller, M. J., Ramella, M.
We describe the ROSAT All-Sky Survey-Center for Astrophysics Loose Systems (RASSCALS), the largest X-ray and optical survey of low mass galaxy groups to date. We draw 260 groups from the combined...
Confirming EIS Clusters. Multi-object Spectroscopy (1999)
Biviano, A., Ramella, M., Boschin, W., Bardelli, S., Scodeggio, M., Da Costa, L. N., ...
Using EFOSC2 at the 3.6m ESO telescope, we obtained redshifts for 68 galaxies in the field of six cluster candidates from the ESO Imaging Survey (EIS). The cluster candidates were selected in the EIS...
Confirming EIS Clusters. Optical and Infrared Imaging (1999)
Olsen, L. F., Jorgensen, H. E., Scodeggio, M., Da Costa, L., Rengelink, R., Nonino, M., ...
Clusters of galaxies are important targets in observationally cosmology, as they can be used both to study the evolution of the galaxies themselves and to constrain cosmological parameters. Here we...
Guzzo, L., Bartlett, J. G., Cappi, A., Maurogordato, S., Zucca, E., Zamorani, G., ...
We present analyses of the two-point correlation properties of the ESP galaxy redshift survey. From the redshift-space correlation function xi(s), we see positive clustering out to separations ~50/h...
The Dynamics of Poor Systems of Galaxies (1999)
Mahdavi, A., Geller, M. J., Boehringer, H., Kurtz, M. J., Ramella, M.
We assemble and observe a sample of poor galaxy systems that is suitable for testing N-body simulations of hierarchical clustering (Navarro, Frenk, & White 1997; NFW) and other dynamical halo models...
The ESO Slice Project (ESP) galaxy redshift survey: VI Groups of Galaxies (1998)
Ramella, M., Zamorani, G., Zucca, E., Stirpe, G. M., Vettolani, G., Balkowski, C., ...
In this paper we identify objectively and analyze groups of galaxies in the recently completed ESP survey. We find 231 groups above the number overdensity threshold delta(rho)/rho=80 in the redshift...
Cluster identification via Voronoi tessellation (1998)
Ramella, M., Nonino, M., Boschin, W., Fadda, D.
We propose an automated method for detecting galaxy clusters in imaging surveys based on the Voronoi tessellation technique. It appears very promising, expecially for its capability of detecting...
A substructure analysis of the A3558 cluster complex (1998)
Bardelli, S., Pisani, A., Ramella, M., Zucca, E., Zamorani, G.
The "algorithm driven by the density estimate for the identification of clusters" (DEDICA, Pisani 1993, 1996) is applied to the A3558 cluster complex in order to find substructures. This complex,...
Cappi, A., Zamorani, G., Zucca, E., Vettolani, G., Merighi, R., Mignoli, M., ...
We present a detailed discussion of the redshift errors associated to the ESO Slice Project measurements. For a subsample of 742 galaxies with redshifts determined both from the absorption lines...
The ESO Slice Project (ESP) galaxy redshift survey: III. The Sample (1998)
Vettolani, G., Zucca, E., Merighi, R., Mignoli, M., Proust, D., Zamorani, G., ...
The ESO Slice Project (ESP) is a galaxy redshift survey extending over about 23 square degrees, in a region near the South Galactic Pole. The survey is ~85% complete to the limiting magnitude...
The Southern Sky Redshift Survey (1998)
Da Costa, L. Nicolaci, Willmer, C. N. A., Pellegrini, P. S., Chaves, O. L., Rite, C., Maia, M. A. G., ...
We report redshifts, magnitudes and morphological classifications for 5369 galaxies with $m_B \leq 15.5$ and 57 galaxies fainter than this limit, in two regions covering a total of 1.70 steradians in...
Scaramella, R., Guzzo, L., Zamorani, G., Zucca, E., Balkowski, C., Blanchard, A., ...
The issue of the approximate isotropy and homogeneity of the observable universe is one of the major topics in modern Cosmology: the common use of the Friedmann-Robertson-Walker [FWR] metric relies...
1E0657-56: A Contender for the Hottest Known Cluster of Galaxies (1998)
Tucker, W., Blanco, P., Rappoport, S., David, L., Fabricant, D., Falco, E. E., ...
We identify the extended Einstein IPC X-ray source, 1E0657-56, with a previously unknown cluster of galaxies at a redshift of $z=0.296$. Optical CCD images show the presence of a gravitational arc in...
De Lapparent, V., Galaz, G., Arnouts, S., Bardelli, S., Ramella, M.
We describe the current status of the ESO-Sculptor Survey. The observational goal has been to produce a new multi-color photometric catalogue of galaxies in a region located near the southern...
Zucca, E., Zamorani, G., Vettolani, G., Cappi, A., Merighi, R., Mignoli, M., ...
(Abridged) The ESO Slice Project (ESP) is a galaxy redshift survey we have completed as an ESO Key-Project over ~23 square degrees, in a region near the South Galactic Pole. The survey is nearly...
The ESO Slice Project (ESP) galaxy redshift survey: I. Description and First Results (1997)
Vettolani, G., Zucca, E., Zamorani, G., Cappi, A., Merighi, R., Mignoli, M., ...
The ESO Slice Project (ESP) is a galaxy redshift survey we have recently completed as an ESO Key-Project. The ESP covers 23.3 square degrees in a region close to the South Galactic Pole. The survey...
Preliminary Results from the ESO Slice Project (ESP) (1994)
Vettolani, G., Zucca, E., Cappi, A., Merighi, R., Mignoli, M., Stirpe, G., ...
We present the first results of a galaxy redshift survey, ESO Slice Project (ESP), we are accomplishing as an ESO Key-Project over about 30 square degrees in a region near the South Galactic Pole....
Preliminary Results from the ESO Slice Project (ESP) (1993)
Vettolani, G., Zucca, E., Cappi, A., Merighi, R., Mignoli, M., Stirpe, G., ...
We present the first results of a galaxy redshift survey, ESO Slice Project (ESP), we are accomplishing as an ESO Key--Project over about 40 square degrees in a region near the South Galactic Pole....
Corkscrew retinal vessels in neurofibromatosis type 1: report of 12 cases
Muci-Mendoza, R, Ramella, M, Fuenmayor-Rivera, D
Aim: To describe a distinctive spectrum of retinal microvascular abnormalities in 12 patients with neurofibromatosis type 1 (NF-1).