Gaia DR2 orbital properties of selected APOGEE giants with anomalously high levels of [N/Fe] in the bulge and halo of the Milky Way

We have used a state-of-the-art orbital integration model in a more realistic gravitational potential, to explore the orbital properties of a sample of 76 selected N-rich stars across the Milky Way, using 6-dimensional information provided by Gaia and the APOGEE-2 survey. Orbits are integrated in the galaxy modelling algorithm \texttt{GravPot16}, which mimics the non-axisymmetric structure of the inner Milky Way. The inclusion of the Galactic bar proved to be essential for the description of the dynamical behavior of N-rich stars in the inner region ($<$ 5 kpc) of the Galaxy. We calculated the more probable orbital elements using the newly measured proper motions from Gaia DR2 with existing line-of-sight velocities from APOGEE-2 survey and spectrophotometric distance estimations from the \texttt{StarHorse} code. We find that most of the N-rich stars, show typically maximum height to the Galactic plane below 1.5 kpc, and develop rather eccentric orbits. Seven of the bulge sample clusters share the orbital properties of the bar/bulge, having perigalactic and apogalatic distances, and maximum vertical excursion from the Galactic plane inside the bar region.