# Studies of Star-forming Complexes in the Galaxies NGC 628, NGC 2976, and NGC 3351

## TL;DR

This study examines the emission properties of star-forming complexes in three high-metallicity galaxies, revealing correlations between various emissions and insights into dust properties and gas kinematics.

## Contribution

It provides a comparative analysis of interstellar matter emissions across different galaxy types and explores the relationship between emission lines, dust, and gas kinematics in star-forming regions.

## Key findings

- Strong correlation between Hα and IR, UV, and HI emissions.
- Less prominent correlation between CO and Hα emissions.
- Increase in velocity scatter correlates with decreased CO line luminosity.

## Abstract

We analyze parameters of the interstellar matter emission in star-forming complexes in the high metallicity galaxies NGC~628, NGC~2976, and NGC~3351, which have different morphological types. The relation between H$\alpha$ emission and emission in CO and HI lines is considered along with the relation between H$\alpha$ emission and dust emission in the infrared range (IR). The fluxes and surface brightnesses in the UV and IR correlate well with H$\alpha$ emission. The HI emission also correlates well with H$\alpha$, while the correlation between the CO and H$\alpha$ emission is much less prominent. The ratio of the fluxes at 8 and 24 $\mu$m decreases with increasing H$\alpha$ flux. This may be due to changes in the properties of the dust ensemble (a decrease in the mass fraction of polycyclic aromatic hydrocarbons) or to changes in excitation conditions. Analysis of the kinematics of the CO lines shows that the CO flux grows with increasing velocity scatter $\Delta V$ when $\Delta V\lesssim70$~km/s. Preliminary evidence for the existence of star-forming complexes with higher values of $\Delta V$ is presented, and the increase in the velocity scatter is accompanied by a decrease in the CO line luminosity of the complex.