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Context.The study of quasar outflows is essential for understanding the connection between active galactic nuclei (AGN) and their host galaxies. We analyzed the VLT/UVES spectrum of quasar SDSS J0932+0840 and identified several narrow and broad outflow components in absorption, with multiple ionization species including Fe II. This places it among the rare class of outflows known as iron low-ionization broad absorption line outflows (FeLoBALs). Aims.We studied one of the outflow components to determine its physical characteristics by determining the total hydrogen column density, the ionization parameter, and the hydrogen number density. Through these parameters, we obtained the distance of the outflow from the central source, its mass outflow rate, and its kinetic luminosity, and we constrained the contribution of the outflow to the AGN feedback. Methods.We obtained the ionic column densities from the absorption troughs in the spectrum and used photoionization modeling to extract the physical parameters of the outflow, including the total hydrogen column density and ionization parameter. The relative population of the observed excited states of Fe IIwas used to model the hydrogen number density of the outflow. Results.We used the Fe IIexcited states to model the electron number density (n_e) and hydrogen number density (n_H) independently and obtainedn_e≃ 10^3.4cm⁻³andn_H≃ 10^4.8cm⁻³. Our analysis of the physical structure of the cloud shows that these two results are consistent with each other. This places the outflow system at a distance of 0.7_−0.4^+0.9kpc from the central source, with a mass flow rate (Ṁ) of 43₋₂₆⁺⁶⁵ M_⊙yr⁻¹and a kinetic luminosity (Ė_k) of 0.7_−0.4^+1.1× 10⁴³erg s⁻¹. This is 0.5_−0.3^+0.7× 10⁻⁴of the Eddington luminosity (L_Edd) of the quasar, and we thus conclude that this outflow is not powerful enough to contribute significantly toward AGN feedback. 

ABSTRACT Cold quasars are a rare population of luminous, unobscured quasars associated with host galaxies that have a high star formation rate. We aimed to study the host galaxies of 64 of these cold quasars in order to probe how the supermassive black holes and host galaxies were co-evolving. We compiled data from the XMM-XXL survey and cross-matched with the VHS, WISE, and HerMES surveys to obtain multiwavelength photometry spanning the X-ray to the infrared and including optical spectroscopy. From the data, we calculated the supermassive black hole’s mass using broad emission from the Mg ii and Hbeta lines. We compared this with the stellar mass of the entire galaxy and found that the black holes are significantly more massive than would be predicted by local relations, indicating that the majority of black hole growth precedes the bulk of the the stellar mass formation. In addition to this, we created a spectral energy distribution for each galaxy to calculate the star formation rate. We compared the star formation rate with the black hole accretion rate and find that the stellar mass is rapidly increasing at a relative rate faster than the black hole growth, supporting the picture where the black hole grows first.