SIMBAD references

Broad infrared spectra (7-200µm) of four NLSy1 galaxies, obtained with the imaging photo-polarimeter (ISOPHOT) on-board ISO, are presented. ISOPHOT data have been analyzed applying a (non standard) method that is described in details. The infrared spectra of the four selected NLSy1 galaxies have been analyzed in order to derive the distribution of luminosities, temperatures, opacities and sizes of the emitting dust. A comparison between infrared (α_3,60) and optical emission line (H_α/H_β and [OIII]/H_β) properties suggests that NLSy1 galaxies suffer different degrees of dust absorption according to the inclination of the line of sight.