Abstract Details

Name: Prasanta Kumar Nayak
Affiliation: Indian Institute of Astrophysics
Conference ID: ASI2017_702
Title : PROPAGATION OF CLUSTER FORMATION IN THE SMC : SIGNATURES OF SMC-LMC-MILKY WAY INTERACTIONS
Authors and Co-Authors : Annapurni Subramaniam (Indian Institute of Astrophysics,Bangalore), Samyaday Choudhury (Yonsei University Observatory, Seoul, Republic of Korea), Ram Sagar (Indian Institute of Astrophysics,Bangalore)
Abstract Type : Poster
Abstract Category : Extragalactic astronomy
Abstract : The Small Magellanic Cloud (SMC) is a neighbouring galaxy (d ~ 60 kpc) to the Milky Way (MW). The recent studies have shown that the SMC had undergone tidal interactions with the MW and Large Magellanic Clouds (LMC). HI distribution (Putman et al. 2003) clearly indicates that the SMC has gone through close encounters with the LMC in the recent past. These interactions are known to disturb the gas and influence star formation events in the SMC. We have parameterised 235 star clusters in the Small Magellanic Cloud (SMC) using the Optical Gravitational Lensing Experiment (OGLE) III survey data. This study brings out 30 newly parameterised clusters. The ages of the clusters are found to be in the range, log(t)= 6.80 - 9.0 (6.6 Myr - 1 Gyr), with an uncertainty of +- 0.20, better than previous age estimations. The colour excess in (V - I) lie between 0.0 to 0.48 mag. Major cluster formation episodes are found to happen at 60 and 400 Myr. We added another 238 clusters to our catalog from previous studies and made a movie based on the propagation (in space and time) of cluster formation. Our study suggests that the southern and the western part of the SMC start forming clusters around 1 Gyr, which later propagates to eastern and northern part in the last 200-300 Myr. The central region of the SMC is found to have continuous cluster formation till date. Presently, the south and the western parts are devoid of cluster formation whereas the northern and eastern regions are actively forming clusters. The propagation of cluster formation is linked to the interaction between the SMC, the LMC and the MW in last one Gyr, and also co-related with the interaction model (Besla et al. 2010,2012). The catalog with parameters, classification, cleaned and isochrone fitted CMDs of 235 clusters, can be further used to understand the hierarchical formation of clusters in selected regions of the SMC.