Ibata, Rodrigo ABellazzini, MChapman, S. C.Dalessandro, EFerraro, F. RIrwin, M. J.Lanzoni, BLewis, Geraint FrancisMackey, AlasdairMiocchi, PVarghese, A2015-12-102041-8205http://hdl.handle.net/1885/60740We report the detection of a stellar density cusp and a velocity dispersion increase in the center of the globular cluster M54, located at the center of the Sagittarius dwarf galaxy (Sgr). The central line-of-sight velocity dispersion is 20.2 ± 0.7 km s-Keywords: Black hole physics; Globular clusters: individual (M54); Stellar dynamics201010.1088/0004-637X/699/2/L1692016-02-24