Related papers: NUV-IR colours of red sequence galaxies in local c…

We combine GALEX near-UV photometry with a volume-limited sample of local (0.005<z<0.037) SDSS DR4 galaxies to examine the composition and the environmental dependencies of the optical and UV-optical colour-magnitude (C-M) diagrams. We find…

We study the slope, intercept, and scatter of the color-magnitude and color-mass relations for a sample of ten infrared red-sequence-selected clusters at z ~ 1. The quiescent galaxies in these clusters formed the bulk of their stars above z…

We report on intriguing photometric properties of Galactic stars observed in the GALEX satellite's far-UV and near-UV bandbasses as well as from the SDSS survey and the Kepler Input Catalog. First, the FUV-NUV color distribution of stars in…

We present recent results from a GALEX investigation of star formation in 16 cooling core clusters of galaxies, selected to span a broad range in both redshift and central cooling time. Initial results demonstrate clear UV excesses in most,…

Using GALEX, UVOT and optical photometry, we explore the prevalence and strength of the UV-upturn in the spectra of quiescent early type galaxies in several nearby clusters. Even for galaxies with completely passive optical colours, there…

We have studied ~2100 early-type galaxies in the SDSS DR3 which have been detected by the GALEX Medium Imaging Survey (MIS), in the redshift range 0 < z < 0.11. Combining GALEX UV photometry with corollary optical data from the SDSS, we…

We present and analyse optical and ultra-violet colours for passive and optically-red Coma cluster galaxies for which we have spectroscopic age and element abundance estimates. Our sample of 150 objects covers a wide range in mass, from…

The rest-frame UV-optical (i.e., NUV-B) color index is sensitive to the low-level recent star formation and dust extinction, but it is insensitive to the metallicity. In this Letter, we have measured the rest-frame NUV-B color gradients in…

CONTEXT:At low redshift, early-type galaxies often exhibit a rising flux with decreasing wavelength in the 1000-2500 \AA{} range, called "UV upturn". The origin of this phenomenon is debated, and its evolution with redshift is poorly…

We present ultraviolet photometry (NUV band, 180--280 nm) of 405 asteroids observed serendipitously by the Galaxy Evolution Explorer (GALEX) from 2003--2012. All asteroids in this sample were detected by GALEX at least twice. Unambiguous…

Although the optical colour-magnitude diagram of galaxies allows one to select red sequence objects, neither can it be used for galaxy classification without additional observational data such as spectra or high-resolution images, nor to…

We investigate the origin of the color-magnitude relation (CMR) observed in cluster galaxies by using a combination of a cosmological N-body simulation of a cluster of galaxies and a semi-analytic model of galaxy formation. The departure of…

Using deep NIR VLT/ISAAC and optical HST/WFPC2 imaging in the fields of the HDFS and MS1054-03, we study the rest-frame UV-to-optical colors and magnitudes of galaxies to z~3. While there is no evidence for a red sequence at z~3, there does…

We present GALEX UV observations of a sample of Low Surface Brightness (LSB) galaxies for which HI data are available, allowing us to estimate their star formation efficiency. We find that the UV light extends to larger radii than the…

We have analyzed the bivariate distribution of galaxies as a function of ultraviolet-optical colors and absolute magnitudes in the local universe. The sample consists of galaxies with redshifts and optical photometry from the Sloan Digital…

We present ultraviolet (UV) integrated colors of 44 Galactic globular clusters (GGCs) observed with the Galaxy Evolution Explorer (GALEX) in both FUV and NUV bands. This data-base is the largest homogeneous catalog of UV colors ever…

Using deep two-band imaging from the Hubble Space Telescope, we measure the color-magnitude relations (CMR) of E/S0 galaxies in a set of 9 optically-selected clusters principally from the Red-Sequence Cluster Survey (RCS) at 0.9 < z < 1.23.…

This work continues our efforts to calibrate model surface brightness luminosities for the study of unresolved stellar populations, through the comparison with data of Magellanic Cloud star clusters. We present here the relation between…

We present a new method of quantifying the mass fraction of young stars in galaxies by analyzing near-ultraviolet (NUV)-optical colors. We focus our attention on early-type cluster galaxies, whose star formation history is at present…

We present GALEX far-ultraviolet (FUV, $\lambda_{eff}$=1538 \AA) and near-ultraviolet (NUV, $\lambda_{eff}$=2316 \AA) surface photometry of 40 early-type galaxies (ETGs) selected from a wider sample of 65 nearby ETGs showing emission lines…