The Cosmic Owl: Twin Active Collisional Ring Galaxies with Starburst Merging Front at $z=1.14$

TL;DR

The Cosmic Owl is a rare twin collisional ring galaxy system at z=1.14, where galaxy collision and AGN jets induce shock-triggered starburst activity, providing insights into galaxy evolution in the early Universe.

Contribution

This paper reports the discovery and detailed analysis of a unique twin collisional ring galaxy system at high redshift, highlighting shock-induced star formation driven by galaxy collision and AGN activity.

Findings

Both galaxies host active galactic nuclei (AGN).

A bipolar radio jet impacts the merging front.

A starburst is triggered by shocks from collision and jet.

Abstract

Galaxy mergers play a critical role in driving galaxy evolution, especially by transforming galaxy morphology, redistributing gas around galaxies, triggering active galactic nuclei (AGN), and stimulating star formation. We present the Cosmic Owl, a galaxy merger at $z=1.14$, identified in the COSMOS field. Deep imaging and spectroscopy from JWST, ALMA, and VLA reveal a complex system of twin collisional ring galaxies, exhibiting nearly identical morphologies. The grism spectra from the JWST COSMOS-3D program confirm that both galaxies host an AGN. A bipolar radio jet from one AGN extends to strike the merging front. In addition, we detect a starburst at the merging front, characterized by luminous extended nebular line emission and a massive cold gas reservoir. This starburst is likely triggered by interstellar shocks induced by galaxy collision and the AGN jet. The twin ring structure of the Cosmic Owl requires further numerical simulations to clarify the precise conditions that lead to the formation of this rare morphology. This system exemplifies how shock-induced star formation, driven by galaxy collision or AGN jet, can act as a crucial mechanism for triggering intense starbursts in the early Universe.