English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Tools annual

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools monthly

Global: Zendy Plus monthly

Presents the access of premium content as premium feature

Premium Content

Global: Zendy Plus annual

Global: Zendy Free Plan

The SDSS Data Release 1 includes 1833 DA white dwarfs (WDs) and forms thelargest homogeneous sample of WDs. This sample provides the best opportunity tostudy the statistical properties of WDs. We adopt a recently establishedtheoretical model to calculate the mass and distance of each WD using theobservational data. Then we adopt a bin-correction method to correct forselection effects and use the 1/V weight-factor method to calculate theluminosity function, the continuous mass function and the formation rate ofthese WDs. The SDSS DA WD sample is incomplete and suffers seriously fromselection effects. After corrections for the selection effects, only 531 WDsremain. From this final sample we derive the most up-to-date luminosityfunction and mass function, in which we find a broad peak of WD masses centeredaround 0.58$M_{\odot}$. The DA WD space density is calculated as$8.81\times10^{-5}pc^{-3}$ and the formation rate is $2.579\times10^{-13}pc^{-3}yr^{-1}$. The statistical properties of the SDSS DA WD sampleare generally in good agreement with previous observational and theoreticalstudies, and provide us information on the formation and evolution of WDs.However, a larger and more complete all-sky WD sample is still needed toexplain some subtle disagreements and unresolved issues.Comment: 16 pages, 20 figures, 3 tables, accepted by Astronomy & Astrophysic

The mass and luminosity functions and the formation rate of DA white dwarfs in the Sloan Digital Sky Survey