Merging gas-rich galaxies that harbor low-luminosity twin quasars at z = 6.05: a promising progenitor of the most luminous quasars

• DOI: 10.48550/arxiv.2405.02468
• Publication Date: 2024-05-03
• Authors: Takuma Izumi; Yoshiki Matsuoka; Masafusa Onoue; Michael A. Strauss; Hideki Umehata; J. D. Silverman; Tohru Nagao; Masatoshi Imanishi; Kotaro Kohno; Yoshiki Toba; K. Iwasawa; Kouichiro Nakanishi; Mahoshi Sawamura; Seiji Fujimoto; Satoshi Kikuta; Toshihiro Kawaguchi; Kentaro Aoki; Tomotsugu Goto
• Keywords: Galaxy mergers; FOS: Physical sciences; Galaxies; Astrophysics; Astrophysics - Astrophysics of Galaxies; 01 natural sciences; Galàxies; QB460-466; Galaxy evolution; Astrophysics of Galaxies (astro-ph.GA); 0103 physical sciences; Galaxy interactions; Quasars; Quàsars

We present ALMA [CII] 158 $\mu$m line and underlying far-infrared continuum emission observations ($0''.57 \times 0''.46$ resolution) toward a quasar-quasar pair system recently discovered at $z = 6.05$ (Matsuoka et al. 2024). The quasar nuclei (C1 C2) are very faint ($M_{\rm 1450} \gtrsim -23$ mag), but we detect bright bridging the 12 kpc between two objects extending beyond them (total luminosity $L_{\rm [CII]} \simeq 6 10^9~L_\odot$). total star formation rate of is $\sim 100$ to 550 $M_\odot$ yr$^{-1}$, with [CII]-based gas mass 10^{11}~M_\odot$. dynamical masses galaxies large ($\sim 9 10^{10}~M_\odot$ for C1 5 C2). There smooth velocity gradient in [CII], indicating that these quasars tidally interacting system. identified dynamically distinct, fast component around C1. Detailed inspection spectrum reveals presence broad wing component, which interpret as indication outflows 600$ km s$^{-1}$. expected loading factor outflows, after accounting multiphase gas, would be $\gtrsim 3-8$, an AGN-driven outflow. Hydrodynamic simulations literature predicted this will evolve luminous \lesssim -26$ starbursting ($\gtrsim 1000~M_\odot$ yr$^{-1}$) coalescence, one most extreme populations early universe.