A momentum conserving accretion disk wind in the narrow line Seyfert 1, I Zwicky 1

TL;DR

This paper reports the detection of a fast, momentum-conserving accretion disk wind in the Seyfert galaxy I Zwicky 1, with detailed spectral analysis revealing its properties and implications for AGN feedback mechanisms.

Contribution

It presents the first detailed characterization of a momentum-conserving accretion disk wind in I Zwicky 1, including its velocity, energetics, and comparison to other AGN winds.

Findings

Detected a broad, blueshifted iron K profile indicating a wind at -0.25c.

The wind's mechanical power is 5-15% of Eddington luminosity.

Upper limits on molecular outflows suggest a non-energy-conserving wind.

Abstract

I Zwicky 1 is the prototype optical narrow line Seyfert 1 galaxy. It is also a nearby ($z=0.0611$), luminous QSO, accreting close to the Eddington limit. XMM-Newton observations of I Zw 1 in 2015 reveal the presence of a broad and blueshifted P-Cygni iron K profile, as observed through a blue-shifted absorption trough at 9 keV and a broad excess of emission at 7 keV in the X-ray spectra. The profile can be well fitted with a wide angle accretion disk wind, with an outflow velocity of at least $-0.25c$. In this respect, I Zw 1 may be an analogous to the prototype fast wind detected in the QSO, PDS 456, while its overall mass outflow rate is scaled down by a factor $\times50$ due to its lower black hole mass. The mechanical power of the fast wind in I Zw 1 is constrained to within $5-15$% of Eddington, while its momentum rate is of the order unity. Upper-limits placed on the energetics of any molecular outflow, from its CO profile measured by IRAM, appear to rule out the presence of a powerful, large scale, energy conserving wind in this AGN. We consider whether I Zw 1 may be similar to a number of other AGN, such as PDS 456, where the large scale galactic outflow is much weaker than what is anticipated from models of energy conserving feedback.