The white dwarf population within 40 pc of the Sun

TL;DR

This study uses population synthesis modeling to analyze the white dwarf population within 40 parsecs of the Sun, successfully matching observed data and providing insights into the star formation history and age of the Solar neighborhood.

Contribution

It introduces a comprehensive Monte Carlo-based population synthesis model that accurately reproduces observed white dwarf luminosity functions and reveals recent star formation episodes.

Findings

Reproduces the bright branch feature of the white dwarf luminosity function.

Estimates the Solar neighborhood's age at approximately 8.9 Gyr.

Identifies a recent star formation episode affecting white dwarf properties.

Abstract

The white dwarf luminosity function is an important tool to understand the properties of the Solar neighborhood, like its star formation history, and its age. Here we present a population synthesis study of the white dwarf population within 40~pc from the Sun, and compare the results of this study with the properties of the observed sample. We use a state-of-the-art population synthesis code based on Monte Carlo techniques, that incorporates the most recent and reliable white dwarf cooling sequences, an accurate description of the Galactic neighborhood, and a realistic treatment of all the known observational biases and selection procedures. We find a good agreement between our theoretical models and the observed data. In particular, our simulations reproduce a previously unexplained feature of the bright branch of the white dwarf luminosity function, which we argue is due to a recent episode of star formation. We also derive the age of the Solar neighborhood employing the position of the observed cut-off of the white dwarf luminosity function, obtaining ~8.9+-0.2 Gyr. We conclude that a detailed description of the ensemble properties of the population of white dwarfs within 40pc of the Sun allows us to obtain interesting constraints on the history of the Solar neighborhood.