Escape from the Bermuda cluster: orphanization by multiple stellar
  ejections
  CONTEXT. Dynamical interactions in young stellar clusters can eject massive
stars early in their lives and significantly alter their mass functions. If all
of the most massive stars are lost, we are left with an orphan cluster.
  AIMS. We study the Bermuda cluster (Villafranca O-014 NW), the most
significant young stellar group in the North America and Pelican nebulae, and
the massive stars that may have been ejected from it to test if it has been
orphaned.
  METHODS. We use Gaia EDR3 parallaxes and proper motions to search for
walkaway/runaway stars in the vicinity of the North America and Pelican
nebulae. The candidates are analyzed with spectroscopy and photometry to assess
their nature and their trajectories are traced back in time to determine at
what time they left the Bermuda cluster.
  RESULTS. We detect three ejection events (Bajamar, Toronto, and HD 201 795
events) that expelled 5, 2, and 2 systems, respectively, or 6, 3, and 3 stars
if we count the individual components in spectroscopic/eclipsing binaries. The
events took place 1.611$\pm$0.011 Ma, 1.496$\pm$0.044 Ma, and 1.905$\pm$0.037
Ma ago, respectively, but our analysis is marginally consistent with the first
two being simultaneous. We detect bow shocks in WISE images associated with
four of the ejected systems. Combining the three events, the Bermuda cluster
has lost >200 M_Sol, including its three most massive stars, so it can be
considered an orphan cluster. One consequence is that the PDMF of the cluster
has been radically altered from its top-heavy initial value to one compatible
with a Kroupa-like function. Another one is that the cluster is currently
expanding with a dynamical time scale consistent with the cause being the
ejection events. A scenario in which the Bermuda cluster was formed in a
conveyor belt fashion over several hundreds of ka or even 1 Ma is consistent
with all the observables.
  [ABRIDGED]
