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The Galactic disk exhibits complex chemical and dynamical substructure thought to be induced by the the bar, spiral arms, and satellites. Here, we explore the chemical signatures of bar resonances in action and velocity space and characterize the differences between the signatures of corotation and higher-order resonances using test particle simulations. Thanks to recent surveys, we now have large homogeneous datasets containing metallicities and kinematics of stars outside the solar neighborhood. We compare the simulations to the observational data from Gaia EDR3 and LAMOST DR5, and find weak evidence for a slow bar that associates the hat moving group with its outer Lindblad resonance and Hercules with corotation. While constraints from current data are limited by their spatial footprint, stars closer in azimuth than the Sun to the bars minor axis show much stronger chemodynamical signatures of the bars outer Lindblad and corotation resonances in test particle simulations. Future datasets with greater azimuthal coverage, including the final Gaia data release, will allow reliable chemodynamical identification of bar resonances.
The second data release of the Gaia mission has revealed a very rich structure in local velocity space. In terms of in-plane motions, this rich structure is also seen as multiple ridges in the actions of the axisymmetric background potential of the G
Bars are common galactic structures in the local universe that play an important role in the secular evolution of galaxies, including the Milky Way. In particular, the velocity distribution of individual stars in our galaxy is useful to shed light on
We use mid-infrared 3.6 and 4.5microns imaging of NGC 3906 from the Spitzer Survey of Stellar Structure in Galaxies (S4G) to understand the nature of an unusual offset between its stellar bar and the photometric center of an otherwise regular, circul
SNO+ is a large liquid scintillator-based experiment located 2km underground at SNOLAB, Sudbury, Canada. It reuses the Sudbury Neutrino Observatory detector, consisting of a 12m diameter acrylic vessel which will be filled with about 780 tonnes of ul
Using a numerical simulation of an isolated barred disc galaxy, we first demonstrate that the resonances of the inner bar structure induce more prominent features in the action space distribution for the kinematically hotter stars, which are less sen