Related papers: White Dwarf based evaluation of the GALEX absolute…

The GALEX (Galaxy Evolution Explorer) spectroscopic survey mode, with a resolution of about 8 A in the FUV (1350 - 1750 A) and about 20 A in the NUV (1950 - 2750 A) is used for a systematic search of Ly-a emitting galaxies at low redshift.…

We have carried out a Galaxy Evolution Explorer (GALEX) Cycle 1 guest investigator program covering 56 square degrees near the Taurus T association and 12 square degrees along the northern edge of the Upper Scorpius OB association. We…

We present ultraviolet photometry for globular clusters (GCs) in M31 from 15 square deg of imaging using the Galaxy Evolution Explorer (GALEX). We detect 200 and 94 GCs with certainty in the near-ultraviolet (NUV; 1750 - 2750 Angstroms) and…

Extragalactic surveys provide significant statistical data for the study of crucial galaxy parameters used to constrain galaxy evolution, e.g. stellar mass (M$_*$) and star formation rate (SFR), under different environmental conditions.…

Although white dwarfs are believed to be the end point of most stellar evolution, unlike main sequence stars, they have not yet been the subject of dedicated time-domain surveys for exoplanets. We discuss how their size and distinctive…

We assess the photometric variability of nine stars with spectroscopic Teff and log(g) values from the ELM Survey that locate them near the empirical extremely low-mass (ELM) white dwarf instability strip. We discover three new pulsating…

The planet-hosting and Sirius-type binary system epsilon Reticulum (HD 27442) is examined from the perspective of its more evolved white dwarf secondary. The stellar parameters are determined from a combination of Balmer line spectroscopy,…

Asteroseismology is a powerful tool to precisely determine the evolutionary status and fundamental properties of stars. With the unprecedented precision and nearly continuous photometric data acquired by the NASA Kepler mission, parameters…

The Galaxy Evolution Explorer (GALEX) imaged the sky in two Ultraviolet (UV) bands, far-UV (FUV) and near-UV (NUV), delivering the first comprehensive sky surveys at these wavelengths. The GALEX database contains FUV and NUV images,…

We present a series of systematic abundance measurements for 89 hydrogen atmosphere (DA-type) white dwarfs with temperatures spanning 16000-77000K drawn from the FUSE spectral archive. This is the largest study to date of white dwarfs where…

In order to recognize environmental effects on the evolution of dwarf galaxies in clusters of galaxies, it is first necessary to quantify the properties of objects which have evolved in relative isolation. With oxygen abundance as the gauge…

We present full evolutionary calculations appropriate for the study of hot hydrogen-deficent DO white dwarfs, PG 1159 stars, and DB white dwarfs. White dwarf sequences are computed for a wide range of stellar masses and helium envelopes on…

We report the discovery of a bright (V ~ 13.7), extremely low-mass white dwarf in a close double degenerate system. We originally selected GALEX J171708.5+675712 for spectroscopic follow-up among a group of white dwarf candidates in an…

We present a comprehensive study for the gamma-ray luminosity function (GLF) of blazars and their contribution to the extragalactic diffuse gamma-ray background (EGRB). Radio and gamma-ray luminosity correlation is introduced to take into…

We measure apparent velocities (v_app) of the Halpha and Hbeta Balmer line cores for 449 non-binary thin disk normal DA white dwarfs (WDs) using optical spectra taken for the ESO SN Ia Progenitor surveY (SPY; Napiwotzki et al. 2001).…

We study ultralight scalar fields with quadratic couplings to Standard-Model fermions and derive strong constraints from white-dwarf mass-radius data. Such couplings source scalar profiles inside compact stars, shift fermion masses, and can…

We have used GALEX and SDSS observations to extract 7 band photometric magnitudes for over 80,000 objects in the vicinity of the North Galactic Pole. Although these had been identified as stars by the SDSS pipeline, we found through fitting…

Some M-dwarfs around F-/G-type stars have been measured to be hotter and larger than predicted by stellar evolution models. Inconsistencies between observations and models need addressing with more mass, radius and luminosity measurements…

We present a model-independent method of quantifying galaxy evolution in high-resolution images, which we apply to the Hubble Deep Field (HDF). Our procedure is to k-correct all pixels belonging to the images of a complete set of bright…

Theoretical stellar evolution models are constructed and tailored to the best known, observationally derived characteristics of metal-poor ([Fe/H]$\sim-2.3$) stars representing a range of evolutionary phases: subgiant HD140283, globular…