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Related papers: The White Dwarf Luminosity Function: The Shape of …

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In this paper we present new and improved data on 38 cool white dwarfs identified by Oppenheimer et al. 2001 (OHDHS) as candidate dark halo objects. Using the high-res spectra obtained with LRIS, we measure radial velocities for 13 WDs that…

The New Luyten Two-Tenths catalog contains a large number of high-proper motion white dwarf candidates that remain to be spectroscopically confirmed. We present new spectroscopic observations as well as SDSS archival spectra of 49 white…

Astrophysics · Physics 2009-11-11 Adela Kawka , Stephane Vennes

We present the techniques and early results of our program to measure the luminosity function for White Dwarfs in the SuperCOSMOS Sky Survey. Our survey covers over three quarters of the sky to a mean depth of I~19.2, and finds ~9,500…

Solar and Stellar Astrophysics · Physics 2009-07-22 N. R. Rowell , N. C. Hambly , P. Bergeron

Beyond its goals related to the extragalactic universe, the Sloan Digital Sky Survey (SDSS) is an effective tool for identifying stellar objects with unusual spectral energy distributions. Here we report on the 53 new magnetic white dwarfs…

Astrophysics · Physics 2009-11-10 Gary D. Schmidt

A detailed analysis of halo white dwarf candidates is presented, which is based on model atmosphere fits to observed energy distributions built from photoelectric or photographic magnitudes. Most of the candidates identified in reduced…

Astrophysics · Physics 2009-11-07 P. Bergeron

We report the discovery of three nearby old halo white dwarf candidates in the Sloan Digital Sky Survey (SDSS), including two stars in a common proper motion binary system. These candidates are selected from our 2800 square degree proper…

Halo white dwarfs can provide important information about the properties and evolution of the galactic halo. In this paper we compute, assuming a standard IMF and updated models of white dwarf cooling, the expected luminosity function, both…

Astrophysics · Physics 2009-10-30 J. Isern , E. Garcia-Berro , M. Hernanz , R. Mochkovitch , S. Torres

How confident are we that all of the nearest white dwarfs (WDs) have been identified? In an effort to answer this question, we have begun an initiative to identify and characterize new nearby WDs, particularly in the southern hemisphere. We…

By selecting astrometric and photometric data from the Sloan Digital Sky Survey (SDSS), the L{\'e}pine & Shara Proper Motion North Catalog (LSPM-North), the Two Micron All Sky Survey (2MASS), and the USNO-B1.0 catalog, we use a succession…

Solar and Stellar Astrophysics · Physics 2015-06-04 Conor Sayres , John P. Subasavage , P. Bergeron , P. Dufour , James R. A. Davenport , Yusra AlSayyad , Benjamin M. Tofflemire

The aim of the Degenerate Objects around Degenerate Objects (DODO) survey is to search for very low mass brown dwarfs and extrasolar planets in wide orbits around white dwarfs via direct imaging. The direct detection of such companions…

Earth and Planetary Astrophysics · Physics 2011-04-05 E. Hogan , M. R. Burleigh , F. J. Clarke

This paper describes the discovery of seven dwarf objects of spectral type `L' (objects cooler than the latest M dwarfs) in commissioning imaging data taken by the Sloan Digital Sky Survey (SDSS). Low-resolution spectroscopy shows that…

Astrophysics · Physics 2009-10-31 SDSS Collaboration , Xiaohui Fan

White dwarfs are among the most common objects in the stellar halo; however, due to their low luminosity and low number density compared to the stars in the discs of the Milky Way, they are scarce in the observable volume. Hence, they are…

Astrophysics of Galaxies · Physics 2017-02-09 Marco C. Lam

We present a catalog of 9316 spectroscopically confirmed white dwarfs from the Sloan Digital Sky Survey Data Release 4. We have selected the stars through photometric cuts and spectroscopic modeling, backed up by a set of visual…

We present a detailed description of the physical properties of our current census of white dwarfs within 40 pc of the Sun, based on an exhaustive spectroscopic survey of northern hemisphere candidates from the SUPERBLINK proper motion…

Solar and Stellar Astrophysics · Physics 2015-05-12 M. -M. Limoges , P. Bergeron , S. Lépine

We increase the spectroscopic completeness of the 100 pc white dwarf sample in the SDSS footprint with 840 additional spectra. Our spectroscopy is 86% complete for white dwarfs hotter than $T_{\rm eff}= 5000$ K, where H$\alpha$ remains…

Solar and Stellar Astrophysics · Physics 2024-12-09 Mukremin Kilic , Pierre Bergeron , Simon Blouin , Adam Moss , Warren R. Brown , Antoine Bedard , Gracyn Jewett , Marcel A. Agueros

As a result of competing physical mechanisms, the atmospheric composition of white dwarfs changes throughout their evolution, a process known as spectral evolution. Because of the ambiguity of their atmospheric compositions and the…

Solar and Stellar Astrophysics · Physics 2019-06-19 Simon Blouin , Patrick Dufour , Christian Thibeault , Nicole F. Allard

A 2.5 x 100 degree region along the celestial equator (Stripe 82) has been imaged repeatedly from 1998 to 2005 by the Sloan Digital Sky Survey. A new catalogue of ~4 million light-motion curves, together with over 200 derived statistical…

The Sloan Digital Sky Survey has allowed us to increase the number of known white dwarfs by a factor of five and consequently the number of known pulsating white dwarfs also by a factor of five. It has also led to the discovery of new types…

Solar and Stellar Astrophysics · Physics 2017-09-13 S. O. Kepler , Alejandra D. Romero

We present the results of a study to discover prospective new white dwarf-L dwarf binaries as identified by their near-infrared excesses in the UKIDSS catalogue. We obtained optical spectra to validate the white dwarf nature for 22 of the…

White dwarfs are the final remnants of low- and intermediate-mass stars. Their evolution is essentially a cooling process that lasts for $\sim 10$ Gyr. Their observed properties provide information about the history of the Galaxy, its dark…

Solar and Stellar Astrophysics · Physics 2016-10-05 Enrique García-Berro , Terry D. Oswalt