Mass models of NGC 6624 without an intermediate-mass black hole
  An intermediate-mass black hole (IMBH) was recently reported to reside in the
centre of the Galactic globular cluster (GC) NGC 6624, based on timing
observations of a millisecond pulsar (MSP) located near the cluster centre in
projection. We present dynamical models with multiple mass components of NGC
6624 - without an IMBH - which successfully describe the surface brightness
profile and proper motion kinematics from the Hubble Space Telescope (HST) and
the stellar mass function at different distances from the cluster centre. The
maximum line-of-sight acceleration at the position of the MSP accommodates the
inferred acceleration of the MSP, as derived from its first period derivative.
With discrete realizations of the models we show that the higher-order period
derivatives - which were previously used to derive the IMBH mass - are due to
passing stars and stellar remnants, as previously shown analytically in
literature. We conclude that there is no need for an IMBH to explain the timing
observations of this MSP.
