Is NGC6752 hiding a double black hole binary in its core ?

Abstract

NGC6752 hosts in its halo PSR J1911-5958A, a newly discovered binary millisecond pulsar which is the most distant pulsar ever known from the core of a globular cluster. Interestingly, its recycling history seems in conflict with a scenario of ejection resulting from ordinary stellar dynamical encounters. A scattering event off a binary system of two black holes with masses in the range of 3-50 solar masses that propelled PSR J1911-5958A into its current peripheral orbit seems more likely. It is still an observational challenge to unveil the imprint(s) left from such a dark massive binary on cluster's stars: PSR J1911-5958A may be the first case.Comment: 2 pages, newpasp.sty. To appear in "New Horizons in Globular Cluster Astronomy", eds. G. Piotto, G. Meylan, G.Djorgovski, M. Riell