MUSE crowded field 3D spectroscopy of over 12,000 stars in the globular cluster NGC 6397 - II. Probing the internal dynamics and the presence of a central black hole

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We present a detailed analysis of the kinematics of the Galactic globular cluster NGC 6397 based on more than ~18,000 spectra obtained with the novel integral field spectrograph MUSE.

• While NGC 6397 is often considered a core collapse cluster, our analysis suggests a flattening of the surface brightness profile at the smallest radii.
• Although it is among the nearest globular clusters, the low velocity dispersion of NGC 6397 of <5km/s imposes heavy demands on the quality of the kinematical data.
• We show that despite its limited spectral resolution, MUSE reaches an accuracy of 1km/s in the analysis of stellar spectra.