White Dwarf Envelopes and Gravitational Redshifts
In March 2026, a manuscript led by graduate student and BUWD member Stefan Arseneau (Arseneau, Hermes, Camisassa, Raddi & Bauer 2026) was accepted laying the foundations to constrain the envelope structure of white dwarfs using gravitational redshifts. The hydrogen envelope mass in most white dwarfs is poorly constrained but critically affects the inferred masses and cooling age of these stars. This work combines precise gravitational redshifts and Gaia-inferred radii for nearly 500 objects to measure the mass–radius relation. The results favor evolutionary models with thick, mass-dependent hydrogen envelopes (e.g., MIST). The manuscript has been accepted in The Astrophysical Journal.