  Globular clusters (GCs), as old as our Galaxy, constantly lose their members
to the field as they cross through the Milky Way (MW). These GC escaped stars
(or escapees) are suggested to contribute significantly to the MW halo. If a
star has left the host GC a long time ago, chemical finger prints, e.g., N
enrichment, may reveal its origin. In this work, we aim to establish dynamical
connections between N-rich field stars recently identified by LAMOST and the
existing MW GCs. By constructing the full action distribution, and combining
with metallicity, we found 29 potential GC progenitors for 15 N-rich field
stars. Particularly, some of them may be related to MW accretion events. On the
other hand, if a star recently left its host GC via tidal evaporation, it still
maintain the kinematic properties of the cluster. Here we identify extra-tidal
candidates based on their spatial locations, proper motions (PMs), and their
position on color-magnitude-diagrams (CMDs). We successfully identified more
than 1600 extra-tidal candidates in the vicinity of six Gaia-Enceladus
(GE)-related GCs (i.e., NGC 1851, NGC 1904, NGC 6205, NGC 6341, NGC 6779, NGC
7089). The density map of the extra-tidal candidates is confirmed to be an
efficient way to find extra-tidal structures. The possible two density peaks at
opposite directions of the inner boundary is a good indicator for long stellar
stream. Among 95 extra-tidal candidates with spectroscopic radial velocities
and metallicity, 54 of them are confirmed to be GC escaped stars, as they share
similar properties as host GCs. These extra-tidal candidates are ideal targets
for follow-up spectroscopic observation, as it greatly improves the scientific
outcome. Once statistically significant number of spectroscopic radial
velocities and metallicities are available, the GC dynamical evolution (e.g.,
mass loss, rotation) can be carefully investigated.
