Arp 220 circumnuclear region JWST/NIRSpec data

We compute the total (including ionized, cold, and hot molecular) outflow mass (~=10^7^M_{sun}_), the mass rate (~=15M_{sun}_/yr), and the energetics ( dEout/dt~=10^42^erg/s) for each nucleus, and we found that the ionized and hot molecular outflowing gas contribute around 2-30% of the total mass and the energy of the outflows, as inferred from the combination of multiwavelength information. We discuss the possible origin of the outflows, finding no compelling evidence to prefer a starburst- or AGN-driven scenario.

Regardless of their nature, outflows in Arp 220 propagate in multiple directions from parsec to kiloparsec scales, potentially impacting a significant portion of the host galaxy. This contrasts with isolated systems where outflows typically follow a more collimated path or are limited to the central region of the galaxy and hence do not affect the interstellar medium throughout the entire galaxy. This study highlights the importance of investigating merging systems with multiwavelength facilities, including JWST NIRSpec IFU, to obtain a comprehensive understanding of feedback mechanisms in galaxy evolution.