SDSS J163459.82+204936.0: A Ringed Infrared-Luminous Quasar with Outflows in both Absorption and Emission Lines

TL;DR

This study presents a detailed multiwavelength analysis of the infrared-luminous quasar SDSS J163459.82+204936.0, revealing complex outflows, vigorous star formation, and a recent galactic collision, illustrating a transitional phase in galaxy evolution.

Contribution

It provides new insights into the physical properties and origins of outflows in a luminous quasar, linking them to host galaxy interactions and transitional evolutionary stages.

Findings

Outflows are located at 48-65 pc from the nucleus.

The quasar exhibits vigorous star formation with SFR ~ 140 Msun/yr.

A recent galactic collision formed an off-centered ring.

Abstract

SDSS J1634+2049 is a local (z = 0.1293) infrared-luminous quasar with LIR= 10^11.91 Lsun. We present a detailed multiwavelength study of both the host galaxy and the nucleus. The host galaxy demonstrates violent, obscured star formation activities with SFR ~ 140 Msun yr^-1, estimated from either the PAH emission or IR luminosity. The optical to NIR spectra exhibit a blueshifted narrow cuspy component in Hb, HeI5876,10830 and other emission lines consistently with an offset velocity of ~900 km/s, as well as additional blueshifting phenomena in high-ionization lines , while there exist blueshifted broad absorption lines (BALs) in NaID and HeI*3889,10830, indicative of the AGN outflows producing BALs and emission lines. Constrained mutually by the several BALs with CLOUDY, the physical properties of the absorption-line outflow are derived as follows: 10^4 < n_H <= 10^5 cm^-3, 10^-1.3 <= U <= 10^-0.7 and 10^22.5<= N_H <= 10^22.9 cm^-2 , similar to those derived for the emission-line outflows. The similarity suggests a common origin. Taking advantages of both the absorption lines and outflowing emission lines, we find that the outflow gas is located at a distance of 48 - 65 pc from the nucleus, and that the kinetic luminosity of the outflow is 10^44-10^46 erg s^-1. J1634+2049 has a off-centered galactic ring on the scale of ~ 30 kpc that is proved to be formed by a recent head-on collision by a nearby galaxy. Thus this quasar is a valuable object in the transitional phase emerging out of dust enshrouding as depicted by the co-evolution scenario.