An X-ray and near-IR spectroscopic analysis of the ULIRG IRAS 05189-2524

We present new, quasi-simultaneous hard X-ray and near-IR spectra of the ultraluminous infrared galaxy IRAS 0.5189-2524, and discuss them together with archival and literature data. The 1.9 Seyfert nucleus is Compton-thin. The near-IR broad lines are seen in transmission, similarly to the X-rays, and the medium along the line of sight has an A(V)/N-H ratio definitely lower than Galactic. The increase in obscuration observed at the latter epoch has DeltaA(V)/DeltaN(H) also less than Galactic, supporting a correlation between the properties of the obscuring matter and its proximity to the center. The measured A(V) is compatible with the broad component of H alpha being seen in transmission, as opposed to scattering, so that most of the observed polarization must be due to dichroism. The bolometric luminosity of the AGN, deduced from the X-ray and line luminosities, falls definitely short of accounting for the IR luminosity of the galaxy consistent with its coolish infrared color.