Detection of IMBHs from Microlensing in Globular Clusters

Abstract

Globular clusters have been long predicted to host intermediate‐mass black holes (IMBHs) in their centres. The growing evidence that some/all Galactic globular clusters (GCs) could harbour middle range (102–104 M⊙) black holes, just as galaxies do, stimulates the searches and the development of new methods for proving their existence. Most of the attempts in search of the central black holes (BHs) are indirect and present enormous observational difficulties due to the crowding of stars in the GCs cores. Here we propose another method of detection—the microlensing of the cluster stars by the central BH.