In the vast expanse of the cosmos, galaxies are not static islands but dynamic entities that interact and influence each other. These interactions can trigger star formation in unexpected places, outside the main disks of galaxies. A team of researchers from the Indian Institute of Astrophysics, including Geethika Santhosh, Rakhi R, Koshy George, and their colleagues, has been studying these extragalactic star-forming regions to understand how different types of galactic interactions affect dust content and star formation.
The researchers focused on two main types of galactic interactions: ram-pressure stripping, where a galaxy moves through a dense intergalactic medium, and gravitational interactions, where galaxies collide or come close to each other. They selected two galaxies undergoing ram-pressure stripping (JO201 and JW100) and two formed through gravitational interactions (NGC 5291 and NGC 7252) for their study. Using high-resolution observations from the Ultraviolet Imaging Telescope onboard AstroSat, they measured dust attenuation and star formation rates in these extragalactic structures.
Dust attenuation is a measure of how much starlight is absorbed by dust in the galaxy. The researchers determined this by calculating the ultraviolet continuum slope (β) using the far-ultraviolet to near-ultraviolet color (FUV-NUV) of the star-forming regions. They then corrected the star formation rates of these regions accordingly. Interestingly, they found that the dust attenuation and dust-corrected star formation rate densities in the ram-pressure stripped tails of JO201 and JW100 were comparable to those in the collisional ring of NGC 5291 and the tidal tails of NGC 7252. This suggests that despite the different formation scenarios, these extragalactic structures share similar dust content and star formation activity.
The findings of this study, published in the journal Astronomy & Astrophysics, provide valuable insights into the processes driving star formation in the universe. While the energy industry may not directly apply these findings, understanding the fundamental processes of star formation and the role of dust in galaxies can contribute to broader scientific knowledge. This research also highlights the importance of high-resolution observations in studying the intricate details of galactic interactions and their consequences. As we continue to explore the cosmos, such studies will be crucial in unraveling the mysteries of the universe and our place within it.
This article is based on research available at arXiv.