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arXiv · 2408.15095

An Eddington Limited Accretion Disk Wind in the narrow line Seyfert 1, PG 1448+273

J. N. Reeves·V. Braito·A. Luminari·D. Porquet·M. Laurenti·G. Matzeu·A. Lobban·S. Hagen
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Abstract

PG 1448+273 is a luminous, nearby ($z=0.0645$), narrow line Seyfert 1 galaxy, which likely accretes close to the Eddington limit. Previous X-ray observations of PG 1448 with XMM-Newton in 2017 and NuSTAR in 2022 revealed the presence of an ultra fast outflow, as seen through its blueshifted iron K absorption profile, where the outflow velocity appeared to vary in the range $0.1-0.3c$. In this work, new X-ray observations of PG 1448 are presented, in the form of four simultaneous XMM-Newton and NuSTAR observations performed in July and August 2023. The X-ray spectra appeared at a similar flux in each observation, making it possible to analyze the mean 2023 X-ray spectrum at high signal to noise. A broad ($\sigma=1$ keV) and highly blue-shifted ($E=9.8\pm0.4$ keV) iron K absorption profile is revealed in the mean spectrum. The profile can be modeled by a fast, geometrically thick accretion disk wind, which reveals a maximum terminal velocity of $v_{\infty}=-0.43\pm0.03c$, one of the fastest known winds in a nearby AGN. As a result, the inferred mass outflow rate of the wind may reach a significant fraction of the Eddington accretion rate.

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J. N. Reeves, V. Braito, A. Luminari, D. Porquet, M. Laurenti, G. Matzeu, A. Lobban, S. Hagen. 2024-08-27. An Eddington Limited Accretion Disk Wind in the narrow line Seyfert 1, PG 1448+273. https://arxiv.org/abs/2408.15095

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