* Astronomy

Title: Cheers results on Mrk 573: Study of deep Chandra observations
Authors: Alessandro Paggi, Junfeng Wang, Giuseppina Fabbiano, Martin Elvis, Margarita Karovska

We present results on Mrk 573 obtained as part of the CHandra survey of Extended Emission-line Regions in nearby Seyfert galaxies (CHEERS). This source features a biconical emission in the soft X-ray band, which is closely related with the Narrow Line Region as mapped by the [O III] emission line; we investigate the properties of soft X-ray emission from this source with new deep observations. Making use of the subpixel resolution of the Chandra/ACIS image and PSF-deconvolution, we resolve and study substructures in each ionising cone: the two cone spectra are fitted with photoionisation model, showing a mildly photoionised phase diffused over the bicone. A thermal collisional gas at about ~ 1 keV appears to be located near the "knots" resolved in radio observations and between the "arcs" resolved in the optical images, and can be interpreted in terms of shock interaction with the galactic plane. The nuclear region features higher ionisation parameter without requiring the presence of thermal gas, and shows a slight flux decrease across the observations {together with an increase in the hydrogen column density}, indicating variability of the AGN. The long exposure allow us to find extended emission up to ~ 7 kpc from the nucleus along the bicone axis{, while significant} emission is also detected in the direction perpendicular to the ionising cones, suggesting the lack of the fully obscuring torus that is prescribed in the AGN unified model, and rather the presence of a clumpy structure not fully covering the line of sight.

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