Probing the Physics of Narrow Line Regions in Active Galaxies IV: Full data release of The Siding Spring Southern Seyfert Spectroscopic Snapshot Survey (S7)

TL;DR

This paper presents the second data release of the S7 survey, providing high-resolution integral field spectra for 131 active galaxies, including new data, emission-line fitting products, and analysis of gas excitation and kinematics.

Contribution

It offers the largest and highest-resolution integral field spectroscopic dataset of active galaxies, with advanced emission-line analysis and neural network-based component fitting.

Findings

Correlation between [FeVII]6087 and [OIII]/Hbeta in Seyfert 1 nuclei

Maps of gas excitation and kinematics for all galaxies

Enhanced spectral resolution and data products for active galaxy studies

Abstract

We present the second and final data release of the Siding Spring Southern Seyfert Spectroscopic Snapshot Survey (S7). Data are presented for 63 new galaxies not included in the first data release, and we provide 2D emission-line fitting products for the full S7 sample of 131 galaxies. The S7 uses the WiFeS instrument on the ANU 2.3m telescope to obtain spectra with a spectral resolution of R = 7000 in the red (540 - 700 nm) and R = 3000 in the blue (350 - 570 nm), over an integral field of 25x38 arcsec^2 with 1x1 arcsec^2 spatial pixels. The S7 contains both the largest sample of active galaxies and the highest spectral resolution of any comparable integral field survey to date. The emission-line fitting products include line fluxes, velocities and velocity dispersions across the WiFeS field of view, and an artificial neural network has been used to determine the optimal number of Gaussian kinematic components for emission-lines in each spaxel. Broad Balmer lines are subtracted from the spectra of nuclear spatial pixels in Seyfert 1 galaxies before fitting the narrow lines. We bin nuclear spectra and measure reddening-corrected nuclear fluxes of strong narrow lines for each galaxy. The nuclear spectra are classified on optical diagnostic diagrams, where the strength of the coronal line [FeVII]6087 is shown to be correlated with [OIII]/Hbeta. Maps revealing gas excitation and kinematics are included for the entire sample, and we provide notes on the newly observed objects.