Related papers: Revisiting the luminosity function of single halo …

We collected F606W- and F814W-band time-series data of the Sagittarius low-reddening window in the Galactic bulge with the Advanced Camera far Surveys mounted on the Hubble Space Telescope. We sampled the region approximately every two…

We present the discovery and spectroscopic identification of two very high proper motion ancient white dwarf stars, found in a systematic proper motion survey. Their kinematics and apparent magnitude clearly indicate that they are halo…

We present a grid of evolutionary calculations for metal-poor low-mass stars for a variety of initial helium and metal abundances. The intention is mainly to provide a database for deriving directly stellar ages of halo and globular cluster…

The $Gaia$ mission has provided an unprecedented wealth of information about the white dwarf population of our Galaxy. In particular, our studies show that the sample up to 100\,pc from the Sun can be considered as practically complete.…

We present 594 radial velocity measurements for 71 white dwarfs obtained during our search for binary white dwarfs and not reported elsewhere. We identify three excellent candidate binaries, which require further observations to confirm our…

We derive mass functions (MF) for halo red dwarfs (the faintest hydrogen burning stars) and then extrapolate to place limits on the total mass of halo brown dwarfs (stars not quite massive enough to burn hydrogen). The mass functions are…

Given the importance of white dwarfs (WDs) in many fields of modern astrophysics, the precise knowledge of the actual degree of accuracy of the associated theoretical predictions is a primary task. In the first paper of a series dedicated…

We study properties of dark matter halos at high redshifts z=2-10 for a vast range of masses with the emphasis on dwarf halos with masses 10^7-10^9 Msun/h. We find that the density profiles of relaxed dwarf halos are well fitted by the NFW…

Low mass white dwarfs are the remnants of disrupted red giant stars in binary millisecond pulsars and other exotic binary star systems. Some low mass white dwarfs cool rapidly, while others stay bright for millions of years due to stable…

We present optical spectroscopy for 18 halo white dwarfs identified using photometry from the Canada-France Imaging Survey and Pan-STARRS1 DR1 3$\pi$ survey combined with astrometry from Gaia DR2. The sample contains 13 DA, 1 DZ, 2 DC, and…

(Abriged) We report results of a campaign to image the stellar populations in the halos of highly inclined spiral galaxies, with the fields roughly 10 kpc (projected) from the nuclei. We use the F814W (I) and F606W (V) filters in the Wide…

Context: Understanding the evolution of the dark matter halos of galaxies after they become part of a cluster is essential for understanding the evolution of these satellite galaxies. Aims: We investigate the potential of galaxy-galaxy…

We examine the claim by Oppenheimer et al. (2001) that the local halo density of white dwarfs is an order of magnitude higher than previously thought. As it stands, the observational data support the presence of a kinematically distinct…

We study the stellar population history and chemical evolution of the Milky Way (MW) in a hierarchical LCDM model for structure formation. Using a Monte Carlo method based on the semi-analytical EPS formalism, we reconstruct the merger tree…

White dwarfs are the remnants of low and intermediate mass stars. Because of electron degeneracy, their evolution is just a simple gravothermal process of cooling. Recently, thanks to Gaia data, it has been possible to construct the…

Stellar halos offer fossil evidence for hierarchical structure formation. Since halo assembly is predicted to be scale-free, stellar halos around low-mass galaxies constrain properties such as star formation in the accreted subhalos and the…

White Dwarf luminosities are powerful age indicators, whose calibration should be based on reliable models. We discuss the uncertainty of some chemical and physical parameters and their influence on the age estimated by means of white dwarf…

As part of a global analysis of deep star counts to constrain scenarii of galaxy formation and evolution, we investigate possible links between the galactic spheroid and the dark matter halo. A wide set of deep star counts at high and…

(Summary) Using the conditional luminosity function (CLF) -- the luminosity distribution of galaxies in a dark matter halo -- as the fundamental building block, we present an empirical model for the galaxy distribution. The model…

Short-period (P<1 hour) white dwarf binaries will be the most numerous sources for the space-based gravitational wave detector LISA. Based on thousands of resolved systems, we will be able to constrain binary evolution and provide a new map…