On the Spectrum and Field Strength of the Magnetic White Dwarf GD 229

Abstract

The broad-coverage optical spectrum obtained for the strongly polarized magnetic white dwarf GD 229 reveals additional as well as apparent changes in the locations of known absorption features; the latter are ostensibly due to star rotation in the decade since the last published spectrum. Since (1) the spectrum of magnetized hydrogen is not consistent with observations for any assumed field strength up to at least 2000 MG, and (2) cyclotron transitions cannot account for the complexity and spacing of optical features, the origin of observed features is suggested to be neutral He.