Peeping into recent star formation history of the Magellanic Clouds

TL;DR

This study analyzes the distribution and ages of Cepheids in the Magellanic Clouds to infer a major star formation event around 200 million years ago, likely triggered by galactic interactions.

Contribution

It provides new age distribution data of Cepheids in the Magellanic Clouds and links a significant star formation event to galactic interactions.

Findings

Peak star formation around 200 Myr ago in both Clouds

Asymmetric distribution of Cepheids with high-density structures

Possible link between star formation event and galactic interactions

Abstract

Here, we study the distribution of Fundamental-mode Cepheids in the Magellanic Cloud as a function of their positions and ages using the data from the OGLE~IV survey. Age of the Cepheids are determined through well known period - age relations for the LMC and SMC Cepheids which are used to understand the star formation scenario in the Magellanic Cloud. The age distributions of the Cepheids in LMC and SMC show peak around $155^{+45}_{-35}$ Myr and $224^{+51}_{-42}$ Myr, respectively. This indicates that a major star formation event took place in the Magellanic Cloud at about 200\,Myr ago. It is believed that this event might have been triggered by a close encounter between the two components of the Magellanic Cloud or due to a possible tidal interaction between the Magellanic Cloud and Milky Way galaxy during one of its pericentric passages round the Milky Way. Cepheids are found to be asymmetrically distributed in both the LMC and SMC. A high-density clumpy structure is found to be located towards eastern side of the LMC and south-west direction of the SMC from their respective galactic centres.