A Multi-Survey Approach to White Dwarf Discovery

TL;DR

This paper combines multiple survey data and methods to identify and confirm 54 white dwarfs, including new discoveries and detailed analysis of their physical properties, distances, and variability.

Contribution

It introduces a multi-survey, multi-method approach for white dwarf discovery and characterization, including follow-up spectroscopy and variability confirmation.

Findings

54 white dwarfs identified, 53 are new discoveries

3 white dwarfs within 25 parsecs of Earth

Detection of a pulsating ZZ Ceti white dwarf

Abstract

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 of methods to isolate white dwarf candidates for follow-up spectroscopy. Our methods include: reduced proper motion diagram cuts, color cuts, and atmospheric model adherence. We present spectroscopy of 26 white dwarfs obtained from the CTIO 4m and APO 3.5m telescopes. Additionally, we confirm 28 white dwarfs with spectra available in the SDSS DR7 database but unpublished elsewhere, presenting a total of 54 WDs. We label one of these as a recovered WD while the remaining 53 are new discoveries. We determine physical parameters and estimate distances based on atmospheric model analyses. Three new white dwarfs are modeled to lie within 25 pc. Two additional white dwarfs are confirmed to be metal-polluted (DAZ). Follow-up time series photometry confirms another object to be a pulsating ZZ Ceti white dwarf.