The Search for Intermediate-mass Black Holes in Globular Clusters

16 Apr

[2012Msngr.147…21L] Lützgendorf, N.; Kissler-Patig, M.; de Zeeuw, T.; Baumgardt, H.; Feldmeier, A.; Gebhardt, K.; Jalali, B.; Neumayer, N.; Noyola, E.

Screen Shot 2015-04-16 at 17.06.55Intermediate-mass black holes (IMBHs) fill the gap between supermassive and stellar-mass black holes and they could act as seeds for the rapid growth of supermassive black holes in early galaxy formation. Runaway collisions of massive stars in young and dense stellar clusters could have formed IMBHs that are still present in the centres of globular clusters. We have resolved the central dynamics of a number of globular clusters in our Galaxy using the FLAMES integral-field spectrograph at the VLT. Combining these data with photometry from HST and comparing them to analytic models, we can detect the rise in the velocity dispersion profile that indicates a central black hole. Our homogeneous sample of globular cluster integral-field spectroscopy allows a direct comparison between clusters with and without an IMBH.