Optical spectroscopy of local type-1 AGN LINERs

The Balmer emission originated in the broad line region (BLR) of active galactic nuclei (AGNs) could be either weak and difficult to detect, or even absent, for low luminosity AGNs,  as low ionization nuclear emission-line regions (LINERs). This makes LINERs challenging to fit in the AGN unification scheme. Moreover, a long debate can be found in the literature proposing different ionization sources at the origin of optical emission lines and no universal agreement has been reached.
In this talk, I will present the novel results from our recent study of the 22 local (z < 0.025) type-1 LINERs from the Palomar Survey, on the basis of optical long-slit spectroscopic observations taken with TWIN/CAHA, ALFOSC/NOT and HST/STIS (Cazzoli et al. 2018). We explored the AGN-nature of nearby type-1 LINERs by studying the broad (BLR-originated) Hα component. Then, we derived reliable interpretation for the different component of emission lines by studying their kinematics and ionization mechanism. Finally, we studied the neutral gas in the nuclei of these LINERs by modeling of the NaD absorption.

Date: 
06/09/2018 - 12:30
Speaker: 
Dr. Sara Cazzoli
Filiation: 
IAA-CSIC, Spain


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