From the spectral analysis of a broadband (0.1-200 keV) 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 2 pi; b) the power law is affected by a cut off with e-folding energy about 270 keV, the fourth individual object so far where this property has been firmly detected; c) two absorption features at about 0.7 and 1 keV 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.
Perola, G.c., Matt, G., Cappi, M., Dal Fiume, D., Fiore, F., Guainazzi, M., et al. (1999). X-ray spectral components from a broad band BeppoSAX observation of the Seyfert galaxy IC 4329A. ASTRONOMY & ASTROPHYSICS, 351(3), 937-944.
X-ray spectral components from a broad band BeppoSAX observation of the Seyfert galaxy IC 4329A
MATT, Giorgio;
1999-01-01
Abstract
From the spectral analysis of a broadband (0.1-200 keV) 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 2 pi; b) the power law is affected by a cut off with e-folding energy about 270 keV, the fourth individual object so far where this property has been firmly detected; c) two absorption features at about 0.7 and 1 keV 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.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
