Associated Far-Ultraviolet Absorption Lines in the Narrow-Line Seyfert 1 Galaxy Markarian 478

Markarian 478 (Mrk 478)is one of the prototype narrow-line Seyfert 1 galaxies. We present far-ultraviolet spectra of Mrk 478 obtained in 2001 January with the Far Ultraviolet Spectroscopic Explorer.Our data span the observed wavelength range 915-1185 • with a resolution of～20kms^-1.The spectrum shows a blue continuum, and strong emission lines at O Ⅵ λλ1032, 1038, N Ⅲλ989, and C Ⅲλ977.Associated absorption lines are present on the blue wings of the high-ionization emission doublet O Ⅵ λλ1032, 1038 and Lyβ, and no intrinsic absorption appears in N Ⅲ and C Ⅲ emission profiles.These intrinsic absorption features are resolved into five distinct kinematic components, covering rest-frame velocities from-2300 to 370kms^-1, with respect to the systemic redshift of z_em=0.0774.