2025/12/04 by Lin, Shuting, Feng, Siyi, Zhang, Zhi-Yu +14
#Astrophysics of Galaxies (astro-ph.GA) #FOS: Physical sciences
paper · doi:10.48550/arxiv.2512.04891
We aim to investigate the interplay between dense molecular gas, star formation, and active galactic nucleus (AGN) feedback in the luminous infrared galaxy (LIRG) NGC 1068 at sub-kiloparsec scales. We present the HCN (4-3) and HCO+ (4-3) maps of NGC 1068, obtained with JCMT as part of the Mapping the dense molecular gas in the strongest star-forming galaxies (MALATANG) project, and perform spatially resolved analyses of their correlations with infrared luminosity and soft X-ray emission. Spatially resolved relations between the luminosities of infrared dust emission and dense molecular gas tracers (L\rm IR-L'\rm dense) are found to be nearly linear, without clear evidence of excess contributions from AGN activity. The spatially resolved X-ray emission (L\rm gas0.5-2 keV) displays a radially-dependent twofold correlation with the star formation rate (SFR), suggesting distinct gas-heating mechanisms between the galaxy center and the outer regions. A super-linear scaling is obtained in galactic center regions with SFR surface density (Σ\rm SFR) > 8.2 × 10-6 M_\odot yr-1 kpc-2: log(L\rm gas0.5-2 keV/erg s-1) = 2.2 log(SFR/M_\odot yr-1) + 39.1. We further found a statistically significant super-linear correlation (β= 1.34 ± 0.86) between L\rm gas0.5-2 keV/SFR and HCN(4-3)/CO(1-0) intensity ratio, whereas no such trend is seen for HCO+(4-3)/CO(1-0) or CO(3-2)/CO(1-0). These findings indicate that AGN feedback does not dominate star formation regulation on sub-kiloparsec scales, and that the excitation of dense gas traced by HCN (4-3) may be more directly influenced by high-energy feedback processes compared to HCO+ (4-3) and CO (3-2).