The White Dwarf Luminosity Functions from the Pan-STARRS 1 3{\pi} Steradian Survey

TL;DR

This study constructs detailed white dwarf luminosity functions for the Milky Way's disc and halo using Pan-STARRS 1 data, employing advanced methods to improve accuracy and account for uncertainties and reddening.

Contribution

It presents a new large-scale analysis of white dwarf populations with refined techniques for density estimation and uncertainty handling.

Findings

Disc-to-halo white dwarf ratio of about 100

Constructed luminosity functions covering 83% of the sky

Improved accuracy through Voronoi tessellation and reddening correction

Abstract

A large sample of white dwarfs is selected by both proper motion and colours from the Pan-STARRS 1 3{\pi} Steradian Survey Processing Version 2 to construct the White Dwarf Luminosity Functions of the discs and halo in the solar neighbourhood. Four-parameter astrometric solutions were recomputed from the epoch data. The generalised maximum volume method is then used to calculate the density of the populations. After removal of crowded areas near the Galactic plane and centre, the final sky area used by this work is 7.833 sr, which is 83% of the 3{\pi} sky and 62% of the whole sky. By dividing the sky using Voronoi tessellation, photometric and astrometric uncertainties are recomputed at each step of the integration to improve the accuracy of the maximum volume. Interstellar reddening is considered throughout the work. We find a disc-to-halo white dwarf ratio of about 100.