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

Monica Colpi·Alessia Gualandris·Andrea Possenti
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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.

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Monica Colpi, Alessia Gualandris, Andrea Possenti. 2002-09-19. Is NGC6752 hiding a double black hole binary in its core ?. https://arxiv.org/abs/astro-ph/0209393

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