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Related papers: High-velocity white dwarfs: thick disk, not dark m…

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Dwarf galaxies populating the Galactic halo are assumed to host the largest fractions of dark matter, as calculated from their velocity dispersions. Their major axes are preferentially aligned with the Vast Polar Structure (VPOS) that is…

Astrophysics of Galaxies · Physics 2018-06-27 Francois Hammer , Yanbin Yang , Frederic Arenou , Carine Babusiaux , Jianling Wang , Mathieu Puech , Hector Flores

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 a magnitude and proper motion limited catalogue of ~10,000 white dwarf candidates, obtained from the SuperCOSMOS Sky Survey by means of reduced proper motion selection. This catalogue extends to magnitudes r~19.75 and proper…

Astrophysics of Galaxies · Physics 2011-04-21 Nicholas Rowell , Nigel Hambly

We present the mass distribution for all S/N > 15 pure DA white dwarfs detected in the Sloan Digital Sky Survey up to Data Release 12, fitted with Koester models for ML2/alpha=0.8, and with Teff > 10 000 K, and for DBs with S/N >10, fitted…

Solar and Stellar Astrophysics · Physics 2016-10-04 S. O. Kepler , Detlev Koester , Alejandra Daniela Romero , Gustavo Ourique , Ingrid Pelisoli

Microlensing events observed in the line of sight toward the LMC indicate that a significant fraction of the mass of the dark halo of the Galaxy is probably composed of white dwarfs. In addition, white dwarf sequences have now be observed…

Astrophysics · Physics 2009-10-31 D. Saumon , S. B. Jacobson

White dwarfs carry information on the structure and evolution of the Galaxy, especially through their luminosity function and initial-to-final mass relation. Very cool white dwarfs provide insight into the early ages of each population.…

By selecting in the RAVE-DR4 survey the stars located between 1 and 2 kpc above the Galactic plane, we question the consistency of the simplest three-component model (thin disc, thick disc, halo) for the Milky Way. We confirm that the…

We present a new empirical relation between galaxy dark matter halo mass (${\rm M_{halo}}$) and the velocity along the flat portion of the rotation curve (${\rm V_{flat}}$), derived from 120 late-type galaxies from the SPARC database. The…

Astrophysics of Galaxies · Physics 2018-11-07 Harley Katz , Harry Desmond , Stacy McGaugh , Federico Lelli

Using stellar population synthesis techniques, we explore the photometric signatures of white dwarf progenitor dominated galactic halos, in order to constrain the fraction of halo mass that may be locked-up in white dwarf stellar remnants.…

Astrophysics · Physics 2009-11-10 H. -c. Lee , B. K. Gibson , Y. Fenner , C. B. Brook , D. Kawata , A. Renda , J. Holopainen , C. Flynn

We study the vertical stellar distribution of the Milky Way thin disk in detail with particular focus on the outer disk. We treat the galactic disk as a gravitationally coupled, three-component system consisting of stars, atomic hydrogen…

Astrophysics of Galaxies · Physics 2018-10-03 Suchira Sarkar , Chanda J Jog

The orbital motions of halo stars in the Milky Way reflect the orbital motions of the progenitor systems in which they formed, making it possible to trace the mass-assembly history of the Galaxy. Direct measurement of three-dimensional…

Astrophysics of Galaxies · Physics 2015-06-12 Kohei Hattori , Yuzuru Yoshii , Timothy C. Beers , Daniela Carollo , Young Sun Lee

We model the mass distributions of 40 high surface brightness spiral galaxies inside their optical radii, deriving parameters of mass models by matching the predicted velocities to observed velocity maps. We use constant mass-to-light disk…

Astrophysics · Physics 2009-11-10 Eric I. Barnes , J. A. Sellwood , Arthur Kosowsky

Here, we present near-infrared spectroscopic observations of 15 helium atmosphere, metal-rich white dwarfs obtained at the NASA Infrared Telescope Facility. While a connection has been demonstrated between the most highly polluted, hydrogen…

Astrophysics · Physics 2009-11-13 Mukremin Kilic , J. Farihi , Atsuko Nitta , S. K. Leggett

We use three different techniques to identify hundreds of white dwarf (WD) candidates in the Next Generation Virgo Cluster Survey (NGVS) based on photometry from the NGVS and GUViCS, and proper motions derived from the NGVS and the Sloan…

Precise abundance ratios are determined for 94 dwarf stars with 5200 < Teff < 6300 K, -1.6 < [Fe/H] < -0.4, and distances D < 335 pc. Most of them have halo kinematics, but 16 thick-disk stars are included. Equivalent widths of atomic lines…

Astrophysics of Galaxies · Physics 2015-05-18 Poul E. Nissen , William J. Schuster

A popular interpretation of recent microlensing studies of the line of sight towards the Large Magellanic Cloud invokes a population of old white dwarf stars in the Galactic halo. Below I review the basic properties of old white dwarf stars…

Astrophysics · Physics 2007-05-23 Brad M. S. Hansen

Observational evidence has suggested the possibility of a Galactic halo which is dominated by white dwarfs (WDs). While debate continues concerning the interpretation of this evidence, it is clear that an initial mass function (IMF) biased…

Astrophysics · Physics 2009-11-07 Chris B. Brook , Daisuke Kawata , Brad K. Gibson

We use a series of N-body/smoothed particle hydrodynamics simulations and analytic arguments to show that the presence of an effective temperature floor in the interstellar medium at T_F ~ 10^4 K naturally explains the tendency for low-mass…

Astrophysics · Physics 2009-11-16 Tobias Kaufmann , Coral Wheeler , James S. Bullock

The destiny of planetary systems through the late evolution of their host stars is very uncertain. We report a metal-rich gas disk around a moderately hot and young white dwarf. A dynamical model of the double-peaked emission lines…

Astrophysics · Physics 2007-05-23 B. T. Gaensicke , T. R. Marsh , J. Southworth , A. Rebassa-Mansergas

Mass models for a sample of 18 late-type dwarf and low surface brightness galaxies show that in almost all cases the contribution of the stellar disks to the rotation curves can be scaled to explain most of the observed rotation curves out…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 R. A. Swaters , R. Sancisi , T. S. van Albada , J. M. van der Hulst
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