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 elementsusing the newly measured proper motionsfrom 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 planebelow 1.5 kpc, and develop rather eccentric orbits. Seven of the bulgesample clusters share the orbital properties of the bar/ bulge, having perigalactic and apogalatic distances, and maximum vertical excursion from the Galactic planeinside the bar region.