Structures Of Dust and gAs (SODA): Constraining the innermost dust properties of II Zw96 with JWST observations of H$_2$O and CO

• DOI: 10.48550/arxiv.2401.02763
• Publication Date: 2024-01-01
• Authors: I. García-Bernete; M. Pereira-Santaella; E. González-Alfonso; D. Rigopoulou; A. Efstathiou; Fergus R. Donnan; N. Thatte

We analyze JWST NIRSpec$+$MIRI/MRS observations of the infrared (IR) gas-phase molecular bands most enshrouded source (D1) within interacting system and luminous IR galaxy II Zw 096. report detection rovibrational lines H$_2$O $\nu_2$=1-0 ($\sim$5.3-7.2 $\mu$m) $^{12}$CO $\nu$=1-0 ($\sim$4.45-4.95 in D1. The CO band shows R- P-branches emission spectrum P-branch R-branch absorption. absorption unveils an IR-bright embedded compact D1 broad component features a highly turbulent environment. From both bands, we also identified extended intense star-forming (SF) activity associated with circumnuclear photodissociation regions (PDRs), consistent strong ionised 7.7 $\mu$m polycyclic aromatic hydrocarbon this source. By including 4.5-7.0 continuum information derived from analysis, modelled dusty torus SF component. is very (diameter $\sim$3 pc at 5 characterised by warm dust ($\sim$ 370 K), giving surface brightness $\sim$3.6$\times$10$^{8}$ L$_{\rm sun}$/pc$^2$. This result suggests presence dust-obscured active galactic nucleus (AGN) D1, which has exceptionally high covering factor that prevents direct AGN emission. Our results open new way to investigate physical conditions inner tori via modelling observed bands.