The following document lists the file abstract/JCLAVEL_NLS1.abs
from catalogue VI/111.
A plain copy of the file
(without headers/trailers) may be downloaded.
===================================================================== ===================================================================== We propose to observe a sample of Narrow Line Seyfert 1 galaxies (or quasars) (NLS1) with CAM, PHT-C and for the brightest galaxies, PHT-S and PHT-P. NLS1 are a peculiar sub-class of Active Galactic Nuclei (AGN) characterized by narrow permitted lines and a strong and steep soft X-ray excess. About 45 such objects have been identified to date, 33 of which are still observable with ISO. Two schemes have been proposed to explain the correlation between line width and steepness of the soft X-ray slope: either (1) NLS1 are normal S1 seen close to pole-on with the further assumption that the accretion disk is geometrically thick or (2) NLS1 represent a short lived episode of high accretion rate in otherwise low mass AGN. Different Spectral Energy Distribution (SED) are predicted by the two models. The aim of our proposal is to map the NLS1 (SED) and compare it with that of normal Seyfert 1 so as to test the validity of the models. This proposal is an extension of our GT programme SEYFERT/JCLAVEL to observe the 2-12 micron spectrum of normal AGN in the CfA sample with PHT-S and CAM.