Spectroscopic Characterization of WD J000801.25-350450 and Its Two Comoving Companions

March 2026 • 2026AJ....171..171J

Authors • Jałowiczor, Peter A. • Bickle, Thomas P. • Kirkpatrick, J. Davy • Casewell, Sarah L. • Gentile Fusillo, Nicola • Schneider, Adam C. • Gagné, Jonathan • Faherty, Jacqueline K. • Meisner, Aaron M. • Kuchner, Marc J. • Burgasser, Adam J. • Rothermich, Austin • Bravo, Alexia • Hyogo, Michiharu • Popinchalk, Mark • Brown, Alex J. • Rebassa-Mansergas, Alberto • Murillo-Ojeda, Raquel • The Backyard Worlds: Planet 9 Collaboration

Abstract • We present new spectroscopic data for Gaia DR3 2309499817384726016 (WD 0008-350A) and its two wide, comoving, low-mass companions. We confirm the white dwarf is a hydrogen rich DA, with T_eff = 6200 ± 90 K and a mass of 0.63 ± 0.03 M_⊙, close to that of the average white dwarf. Near-infrared spectra of the two stellar companions to WD 0008-350A reveal that the inner companion is an M dwarf, exhibiting a spectral type of M8. Furthermore, the outer companion is identified as a possible M6 + M9 binary. This paper examines the evidence which suggests the system may be quadruple.

Links

• ELECTR https://doi.org/10.3847/1538-3881/ae38d3