1999A&A...351..937P

From the spectral analysis of a broadband (0.1-200keV) BeppoSAX observation of the Seyfert 1 galaxy IC 4329A, the main results obtained are: a) the amount of reflection, together with the intensity of the iron K line, indicate a geometry with a solid angle substantially less than 2π; b) the power law is affected by a cut off with e-folding energy about 270keV, the fourth individual object so far where this property has been firmly detected; c) two absorption features at about 0.7 and 1keV are found, the first corresponding to a blend of O vi and O vii, the other to a combination of FeL and NeK edges. Compared to an earlier ASCA observation, when the source was 30% fainter, the values of both the relative amount of reflection and the warm absorber ionization degree are significantly lower: the comparison is suggestive of sizeable delay effects in this object, due to geometrical factors in the reflection, and to relaxation to equilibrium states in the ionization of the absorber.