相关论文: Blueshifted galaxies in the Virgo Cluster
In order to investigate the nature of dwarf Low Surface Brightness (LSB) galaxies we have undertaken a deep B and I band CCD survey of a 14 sq degree strip in the Virgo Cluster and applied a Fourier convolution technique to explore its…
We present a study of the stellar populations of globular clusters (GCs) in the Virgo Cluster core with a homogeneous spectroscopic catalog of 692 GCs within a major axis distance $R_{\rm maj} = $ 840 kpc from M87. We investigate radial and…
The distributions of the pairwise line-of-sight velocity between galaxies and their host clusters are segregated according to the galaxy's colour and morphology. We investigate the velocity distribution of red-spiral galaxies, which…
We present the results of an extensive spectroscopic survey of RX J0152.7-1357, one of the most massive distant clusters of galaxies known. Multi-object spectroscopy, carried out with FORS1 and FORS2 on the ESO Very Large Telescope (VLT),…
We revisit the color-magnitude relation (CMR) of the Virgo cluster early-type galaxies in order to explore its alleged non-linearity. To this aim, we reanalyze the relation already published from data obtained within the ACS Virgo Cluster…
Peculiar velocities thoughout the region of the local supercluster are reconstructed by two different orbit-retracing methods. The requirement of the optimal correlation between the radial components of reconstructed velocities and the…
We present a catalogue of velocities for 466 galaxies in the direction of the cluster Abell 496, in a region covering about 160' x 160' (9.2 x 9.2 Mpc for an average redshift for Abell 496 of 0.0331, assuming H$_0$=50 km s$^{-1}$…
In the last decade we witness an advent of new types of dwarf stellar systems in cluding ultra-compact dwarfs, ultra-faint dwarf spheroidals, and exotic globular clusters, breaking the old simple paradigm for dwarf galaxies and globular…
Redshifts of several galaxies thought to be associated with NGC 326 are determined. The results confirm the presence of a cluster and find a mean redshift of z = 0.0477 +/- 0.0007 and a line-of-sight velocity dispersion sigma_{z} = 599…
We present Hubble Space Telescope/WFPC2 images of sixteen dwarf galaxies as part of our snapshot survey of nearby galaxy candidates. We derive their distances from the luminosity of the tip of the red giant branch stars with a typical…
It has been suspected for nearly 50 years that clusters of galaxies contain a population of intergalactic stars, ripped from galaxies during cluster formation or when the galaxies' orbits take them through the cluster center. Support for…
As a part of our galaxy-cluster redshift survey, we present a set of 80 new velocities in the 4 clusters Abell 376, Abell 970, Abell 1356, and Abell 2244, obtained at Haute-Provence observatory. This set now completes our previous analysis,…
Aperture synthesis observations of two HI cloud complexes located in the periphery of the Virgo galaxy cluster are presented. These low HI-mass clouds ($M_{HI}<$ 10$^{9}$) are seen projected on the M region of the western Virgo cluster,…
We use a combination of deep optical (gri) and near-infrared (H) photometry to study the radially-resolved colours of a broad sample of 300 Virgo cluster galaxies. For most galaxy types, we find that the median g-H colour gradient is either…
For a rotating galaxy, the inner circular-velocity gradient d_{R}V(0) provides a direct estimate of the central dynamical mass density, including gas, stars, and dark matter. We consider 60 low-mass galaxies with high-quality HI and/or…
Early-type dwarfs are the most common galaxy in the local universe, yet their origin and evolution remain a mystery. Various cosmological scenarios predict that dwarf-like galaxies in dense areas are the first to form and hence should be…
We present the first spectroscopic study of the globular clusters (GCs) in the giant elliptical galaxy (gE) M86 in the Virgo cluster. Using spectra obtained in the Multi-Object Spectroscopy (MOS) mode of the Faint Object Camera and…
We study the role of the environment on galaxy evolution using a sample of 868 galaxies in the Virgo cluster and in its surrounding regions selected from the GUViCS Survey with the purpose of understanding the origin of the red sequence in…
The physical relationship between low-excitation gas filaments at ~10^4 K, seen in optical line emission, and diffuse X-ray emitting coronal gas at ~10^7 K in the centers of many galaxy clusters is not understood. It is unclear whether the…
We describe results of a multi-spectral study of a blue compact dwarf galaxy in Virgo. The object was observed with broad-band and H$\alpha$ imaging, UV observations, and radio synthesis. Our data were combined with published optical…