S-PLUS. multiple stellar population in GCs

By probing different spectral ranges affected by different absorption lines using the multi-band photometric survey S-PLUS, we study four GCs - NGC104, NGC288, NGC3201 and NGC7089 - that span a wide range of metallicities. With the combination of broad and narrow-band photometry in 12 different filters from 3485A (u) to 9114A (z), we identified MSPs along the rectified red-giant branch in colour-magnitude diagrams (CMDs) and separated them using a K-means clustering algorithm.

Additionally, we take advantage of the large Field of View of the S-PLUS detector to investigate radial trends in our sample. We report on six colour combinations that can be used to successfully identify two stellar populations in all studied clusters and show that they can be characterised as Na-rich and Na-poor. For both NGC 288 and NGC 7089, their radial profiles show a clear concentration of 2P population.