相关论文: Binary stars and the UVX in early type galaxies

We characterise the stellar masses and star formation rates in a sample of almost 40000 spectroscopically confirmed UV luminous galaxies at 0.3<z<1.0 selected from within the WiggleZ Dark Energy Survey. In particular, we match this UV…

Determining the properties of old stellar populations (those with age >1 Gyr) has long involved the comparison of their integrated light, either in the form of photometry or spectroscopic indexes, with empirical or synthetic templates. Here…

UV observations in the local universe have uncovered a population of early-type galaxies with UV flux consistent with low-level recent or ongoing star formation. We present resolved UV-optical photometry of a sample of 19 SDSS early-type…

We report on a study of 9 nearby star-forming, very low-metallicity galaxies observed by Hubble's COS far-UV spectrograph that can serve as templates of high-z galaxies to be observed by JWST. We find that the nebular spectra of these…

We combine deep UBVRIzJK photometry from the MUSYC survey with redshifts from the COMBO-17 survey to study the rest-frame ultraviolet (UV) properties of 674 high-redshift (0.5<z<1) early-type galaxies, drawn from the Extended Chandra Deep…

The first directly detected gravitational waves (GW 150914) were emitted by two coalescing black holes (BHs) with masses of ~36Msun and ~29Msun. Several scenarios have been proposed to put this detection into an astrophysical context. The…

The UV upturn phenomenon observed in elliptical galaxies is attractive for its potential value as an age indicator of old stellar systems. We present our most recent population models for the UV evolution of elliptical galaxies. We confirm…

We investigate the effects of abundance and age on the mid-UV spectra and Mg_{2} strengths of stellar populations using simple population synthesis models. These models are used to constrain the star formation history of four nearby…

We present deep optical and near-infrared imaging of the rich cluster A2218 at z=0.17. Our optical imaging comes from new multicolour Hubble Space Telescope WFPC2 observations in the F450W (B), F606W (V) and F814W (I) passbands. These…

We study the nature of faint, red-selected galaxies at z ~ 2-3 using the Hubble Ultra Deep Field (HUDF) and Spitzer IRAC photometry. We detect candidate galaxies to H < 26 mag, probing lower-luminosity (lower mass) galaxies at these…

In order to investigate the origin of the far-UV (FUV) flux from the early-type galaxies, Galaxy Evolution Explorer (GALEX) is collecting the UV data for the elliptical-rich clusters at moderate redshifts (z < 0.2) where the dominant FUV…

We report on a complete sample of 7 luminous early-type galaxies in the Hubble Ultra Deep Field (UDF) with spectroscopic redshifts between 1.39 and 2.47 and to K<23 AB. Using the BzK selection criterion we have pre-selected a set of objects…

The upcoming generation of optical spectrographs on four meter-class telescopes, with their huge multiplexing capabilities, excellent spectral resolution, and unprecedented wavelength coverage, will provide high-quality spectra for…

Using evolutionary population synthesis we present integrated colours, integrated spectral energy distributions and absorption-line indices defined by the Lick Observatory image dissector scanner (referred to as Lick/IDS) system, for an…

Multi-color photometry is presented for a large sample of local ellipticals selected by morphology and isolation. The sample uses data from GALEX, SDSS, 2MASS and Spitzer to cover the filters NUV, ugri, JHK and 3.6mum. Various two-color…

We present an analysis of $UBVRI$ data from the Selected Area SA 141. By applying recalibrated methods of measuring ultraviolet excess (UVX), we approximate abundances and absolute magnitudes for 368 stars over 1.3 square degrees out to…

(Abridged) We have identified a population of faint red galaxies from a 0.62 square degree region of the Las Campanas Infrared Survey whose properties are consistent with their being the progenitors of early-type galaxies. The optical and…

We consider the general theoretical problem of ultraviolet light from old stellar populations (t > 2 Gyr), and the interpretation of galaxy spectra at short wavelengths (lamda < 3200A) The sources believed to be responsible for the observed…

We investigate the effect of stellar density on the ultraviolet (UV) emission from M31's globular clusters (GCs). Published far-UV (FUV) and near-UV (NUV) colours from Galaxy Evolution and Explorer (GALEX) observations are used as a probe…

Most stars are members of binaries, and the evolution of a star in a close binary system differs from that of an ioslated star due to the proximity of its companion star. The components in a binary system interact in many ways and binary…