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Mapping Seyfert and LINER Excitation Modes in the Inner kpc of NGC 3393

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 نشر من قبل Peter Maksym
 تاريخ النشر 2016
  مجال البحث فيزياء
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We have mapped the extended narrow line region (ENLR) of NGC 3393 on scales of $rlesssim4^{primeprime}$ ($sim1,$kpc) from the nucleus using emission line images of H$alpha,lambda6563$, [O III]$lambda5007$, and [S II]$lambdalambda6717,6731$ taken with HST as part of the CHandra survey of Extended Emission line Regions in nearby Seyfert galaxies (CHEERS). By mapping these lines onto a spatially resolved Baldwin-Phillips-Terlevich (BPT) diagram, we investigate the impact of feedback from a Compton-thick AGN on its circumnuclear ISM. We find the expected Seyfert-like emission within the ionization bicone ($lesssim3^{primeprime}$; 770 pc). We also find a new, figure 8 shaped LINER cocoon enveloping the bicone and defining a sharp ($lesssim100;$pc) transition between higher and lower ionization zones. These data illustrate the morphological dependence of ionization states of the ENLR relative to bicone and host gas geometries.



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