New Ultracool Companions to Nearby White Dwarfs
Abstract
We conducted a search for new ultracool companions to nearby white dwarfs using multiple methods, including the analysis of colors and examination of images in both the optical and the infrared. Through this process, we identified fifty-one previously unrecognized systems with candidate ultracool companions. Thirty-one of these systems are resolved in at least one catalog, and all but six are confirmed as co-moving companions via common proper motion and consistent parallax measurements (when available). We have followed up four co-moving companions with near-infrared spectroscopy and confirm their ultracool nature. The remaining twenty candidates are unresolved, but show clear signs of infrared excess which is most likely due to the presence of a cold, low-mass companion or a dusty circumstellar disk. Three of these unresolved systems have existing optical spectra that clearly show the presence of a cool stellar companion to the white dwarf primary via spectral decomposition. These new discoveries, along with our age estimates for the primary white dwarfs, will serve as valuable benchmark systems for future characterization of ultracool dwarfs.
Keywords
Cite
@article{arxiv.2412.04597,
title = {New Ultracool Companions to Nearby White Dwarfs},
author = {Alexia Bravo and Adam C. Schneider and Sarah Casewell and Austin Rothermich and Jacqueline K. Faherty and Jenni R. French and Thomas P. Bickle and Aaron M. Meisner and J. Davy Kirkpatrick and Marc J. Kuchner and Adam J. Burgasser and Federico Marocco and John H. Debes and Arttu Sainio and Léopold Gramaize and Frank Kiwy and Peter A. Jalowiczor and Awab Abdullahi},
journal= {arXiv preprint arXiv:2412.04597},
year = {2024}
}
Comments
Accepted to the Astronomical Journal