Peeping into recent star-formation history of Magellanic Clouds

Abstract

We study the distribution of fundamental-mode Cepheids in the Magellanic Clouds as a function of their positions and ages using the data from the OGLE IV survey. The ages 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 Clouds. The age distributions of the Cepheids in LMC and SMC show prominent peaks around $158^{+46}_{-35}$ Myr and $219^{+63}_{-49}$ Myr, respectively. This indicates that a major star-formation event took place in the Magellanic Clouds about 200 Myr ago. It is believed that this episode of enhanced star formation might have been triggered by a close encounter between the two components of the Magellanic Clouds or due to a possible tidal interaction between the Magellanic Clouds and Milky Way galaxy during one of its pericentric passages around the Milky Way. Cepheids are found to be asymmetrically distributed in both the LMC and SMC in an elongated manner. A high spatial density clumpy structure is found to be located towards the eastern side of the LMC and the south-west direction of the SMC from their respective galactic centers.