Issue |
A&A
Volume 563, March 2014
|
|
---|---|---|
Article Number | A47 | |
Number of page(s) | 6 | |
Section | Galactic structure, stellar clusters and populations | |
DOI | https://doi.org/10.1051/0004-6361/201323256 | |
Published online | 05 March 2014 |
A population synthesis study of the luminosity function of hot white dwarfs
1
Departament de Física AplicadaUniversitat Politècnica de
Catalunya,
c/Esteve Terrades 5,
08860
Castelldefels,
Spain
e-mail:
enrique.garcia-berro@upc.edu
2
Institute for Space Studies of Catalonia,
c/Gran Capità 2–4, Edif. Nexus
104, 08034
Barcelona,
Spain
3
Mt. Suhora Observatory, Cracow Pedagogical University,
ul. Podchorazych 2,
30-084
Cracow,
Poland
4
Gemini Observatory, 670 N. A’Ohoku Place, Hilo
HI
96720,
USA
Received:
14
December
2013
Accepted:
7
February
2014
Context. We present a coherent and detailed Monte Carlo simulation of the population of hot white dwarfs. We assess the statistical significance of the hot end of the white dwarf luminosity function and the role played by the bolometric corrections of hydrogen-rich white dwarfs at high effective temperatures.
Aims. We use the most up-to-date stellar evolutionary models and implement a full description of the observational selection biases to obtain realistic simulations of the observed white dwarf population.
Methods. Our theoretical results are compared with the luminosity function of hot white dwarfs obtained from the Sloan Digital Sky Survey (SDSS), for both DA and non-DA white dwarfs.
Results. We find that the theoretical results are in excellent agreement with the observational data for the population of white dwarfs with hydrogen deficient atmospheres (non-DA white dwarfs). For the population of white dwarfs with hydrogen-rich atmospheres (white dwarfs of the DA class), our simulations show some discrepancies with the observations for the brightest luminosity bins, namely those corresponding to luminosities larger than ~10 L⊙. These discrepancies can be attributed to the way in which the masses of the white dwarfs contributing to this luminosity bin have been computed, as most of them have masses smaller than the theoretical lower limit for carbon-oxygen white dwarfs.
Conclusions. We conclude that the way in which the observational luminosity function of hot white dwarfs is obtained is very sensitive to the particular implementation of the method used to derive the masses of the sample. We also provide a revised luminosity function for hot white dwarfs with hydrogen-rich atmospheres.
Key words: stars: luminosity function, mass function / white dwarfs
© ESO, 2014
Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.
Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.
Initial download of the metrics may take a while.