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arXiv · 1408.4549

S7 : Probing the physics of Seyfert Galaxies through their ENLR & HII Regions

Abstract

Here we present the first results from the Siding Spring Southern Seyfert Spectroscopic Snapshot Survey (S7) which aims to investigate the physics of ~140 radio-detected southern active Galaxies with z<0.02 through Integral Field Spectroscopy using the Wide Field Spectrograph (WiFeS). This instrument provides data cubes of the central 38 x 25 arc sec. of the target galaxies in the waveband 340-710nm with the unusually high resolution of R=7000 in the red (530-710nm), and R=3000 in the blue (340-560nm). These data provide the morphology, kinematics and the excitation structure of the extended narrow-line region, probe relationships with the black hole characteristics and the host galaxy, measures host galaxy abundance gradients and the determination of nuclear abundances from the HII regions. From photoionisation modelling, we may determine the shape of the ionising spectrum of the AGN, discover whether AGN metallicities differ from nuclear abundances determined from HII regions, and probe grain destruction in the vicinity of the AGN. Here we present some preliminary results and modelling of both Seyfert galaxies observed as part of the survey.

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Michael A. Dopita, Prajval Shastri, Julia Scharwachter, Lisa J. Kewley, Rebecca Davies, Ralph Sutherland, Preeti Kharb, Jessy Jose, Harish Bhatt, S. Ramya, Elise Hampton, Chichuan Jin, Julie Banfield, Ingyin Zaw, Shweta Srivastava, Bethan James. 2014-08-20. S7 : Probing the physics of Seyfert Galaxies through their ENLR & HII Regions. https://doi.org/10.1017/s1743921314009661

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