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arXiv · 2212.11434

A closer look at NGC 7314 nuclear region: a multiwavelength analysis of the Seyfert nucleus and its surroundings

Patrícia da Silva·R. B. Menezes·Y. Díaz·A. Rodríguez-Ardila·E. López-Navas·P. Arévalo·L. Hernández-García
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Abstract

The central regions of galaxies harbouring active galactic nuclei (AGNs) can be quite complex, especially at high activity, presenting, besides variability, a variety of phenomena related, e.g. to ionization/excitation mechanisms. A detailed study is necessary in order to understand better those objects. For that reason, we performed a multiwavelength analysis of the nuclear region of the nearby Seyfert galaxy NGC 7314, using an optical data cube obtained with the Integral Field Unit from the Gemini Multi-Object Spectrograph, together with Hubble Space Telescope images, X-ray data from the XMM-Newton and the Nuclear Spectroscopic Telescope Array and radio data from Atacama Large Millimeter/Submillimeter Array. The goals were to study the nuclear and circumnuclear emission, the emission of the AGN and the gas kinematics. The optical spectrum shows the emission of a Seyfert nucleus, with broad components in the H$α$ and H$β$ emission lines, characterising a type 1 AGN, with a spectrum rich in coronal emission lines. The spatial morphology of the [OIII]$λ$5007 suggests the presence of an ionization cone, west of the nucleus, meanwhile the east cone seems to be obscured by dust. An extended [FeVII]$λ$6087 emission was also detected, which could be possibly explained by a scenario involving photoionization+shocks mechanisms. X-rays analyses showed that there are variations in the flux; however, we did not detect any variations in the column density along the line of sight. Its variability may be a consequence of changes in the AGN accretion rate.

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Patrícia da Silva, R. B. Menezes, Y. Díaz, A. Rodríguez-Ardila, E. López-Navas, P. Arévalo, L. Hernández-García. 2022-12-23. A closer look at NGC 7314 nuclear region: a multiwavelength analysis of the Seyfert nucleus and its surroundings. https://doi.org/10.1093/mnras%2Fstac3454

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