X-ray Source Populations in NGC 3532 and Other Intermediate Age Star Clusters

Intermediate-age open clusters offer opportunities to constrain the evolution of massive stars and detect compact objects, including high mass white dwarfs, neutron stars, and black holes in binaries. We performed a multi-wavelength analysis of CXO sources in the 300 Myr open cluster NGC 3532 using the Gaia eDR3, VPHAS+, 2MASS, and WISE catalogs, where we used our random-forest machine-learning pipeline to classify 131 sufficiently bright X-ray sources based on their multi-wavelength features. Most sources were identified as coronally-active low mass stars, but some candidate compact objects were also found. We discuss factors affecting the accuracy and confidence of our classifications, as well as information and assumptions that can improve the classifications. Additionally, we present the results of similar analyses for other nearby star clusters with ages between a few Myr and a few hundred Myr.