The Warm Absorber constrained by the coronal lines in Seyfert 1 galaxies

We present results of the photoionization code IRIS, which calculates the s pectrum emitted by the Warm Absorber (WA) in Seyfert 1 galaxies for a large grid of parameters (density, column density, ionization parameter..). We s how that in Seyfert Is, coronal lines ([Fe X], [Fe XI], [Fe XIV]...), whose emission region shares common characteristics with the WA, could be formed in the WA. Unlike the absorption edges, such as those of O VII and O VIII observed in soft X-rays which are produced by the WA, these lines strongly constrain the physical parameters of the WA, especially the hydrogen densit y. Indeed, in order to avoid producing coronal line equivalent widths large r than observed, a high density (n(H) greater than or equal to 10(10) cm(-3 )) is required for the WA in most cases. This result is obtained for the me an observed Seyfert 1 features, as well as for the case study of MCG-6-30-1 5. It implies that the distance of the WA from the incident radiation sourc e is of the order of that of the Broad Line Region (BLR).