SIMBAD references

The emission-line ratios of LINERs have usually been modelled by radiative shocks or clouds photoionized by power-law continua with a low ionization parameter. Recently it has been suggested that diluted input spectra from stars with T_eff∼50000K can also produce LINERs. We extend these studies by demonstrating that ionizing continua diluted by gaseous absorption (as may be expected in dense interstellar media) can produce LINER spectra. In this way, stars of ∼40000K, which are representative for a normal IMF, can give rise to LINERs with weak [OI] lines. The whole range of LINER-type emission line ratios can e.g. be reached via photoionization from two other types of continua: (i) an average AGN continuum with an EUV bump represented by radiation from a face-on Madau (1988) accretion disk, which is distorted by a gaseous absorber; (ii) an AGN continuum from an inclined accretion disk.