On the Migration Origin of the Hercules Moving Group with GAIA, LAMOST, APOGEE, and GALAH Surveys

Abstract

Using Gaia DR3 data and the wavelet transformation technique, we study the substructures of the Hercules moving group (HMG): Hercules 1 (H1) and Hercules 2 (H2). Spectroscopic survey data from LAMOST, APOGEE, and GALAH are used to obtain metallicities and ages of stars belonging to the HMG. Our analysis leads to several key findings as follows: ($a$) the HMG is on average richer in metallicity than the Galactic disk, with H2 being metal richer than H1; ($b$) the HMG likely has a radial metallicity gradient distinct from that of the disk; ($c$) the HMG is on average older than the disk, with H2 being older than H1; ($d$) the HMG likely has a radial age gradient distinct from that of the disk; and ($e$) the metallicity and age distributions of the HMG depend mainly on the Galactic radius but show no dependence on the azimuthal velocity. Taken all together, we conclude that the HMG is composed primarily of stars undergoing radial migration. We suggest that the HMG is associated with a higher-order dynamical resonance of the bar of the Galaxy.

arXiv comment15 pages, 6 figures. Accepted by ApJ

References in corpus (68)

• Array Programming with NumPy
• The Gaia mission
• The Astropy Project: Sustaining and Growing a Community-oriented Open-source Project and the Latest Major Release (v5.0) of the Core Package
• Gaia Data Release 3: Summary of the content and survey properties
• Radial Mixing in Galactic Discs
• The First Data Release (DR1) of the LAMOST general survey
• The GALAH+ Survey: Third Data Release
• A dynamically young and perturbed Milky Way disk
• The Effect of the Outer Lindblad Resonance of the Galactic Bar on the Local Stellar Velocity Distribution
• Riding the Spiral Waves: Implications of Stellar Migration for the Properties of Galactic Disks
• Local kinematics of K and M giants from Coravel/Hipparcos/Tycho-2 data. Revisiting the concept of superclusters
• Gaia Data Release 2: Mapping the Milky Way disc kinematics
• A New Mechanism for Radial Migration in Galactic Disks: Spiral-Bar Resonance Overlap
• Footprints of the Sagittarius dwarf galaxy in the $Gaia$ data set
• Order and chaos in the local disc stellar kinematics induced by the Galactic bar
• Radial migration in galactic disks caused by resonance overlap of multiple patterns: Self-consistent simulations
• Evolution of Galactic Discs: Multiple Patterns, Radial Migration and Disc Outskirts
• The stellar velocity distribution in the solar neighbourhood
• The Effect of Spiral Structure on the Stellar Velocity Distribution in the Solar Neighborhood
• Constraints on the Galactic Bar from the Hercules stream as traced with RAVE across the Galaxy
• Disentangling the Hercules stream
• Revisiting the Tale of Hercules: how stars orbiting the Lagrange points visit the Sun
• Understanding the spiral structure of the Milky Way using the local kinematic groups
• Disk heating by more than one spiral density wave
• Transient spiral structure and the disc velocity substructure in Gaia DR2
• The Pattern Speed of the Galactic Bar
• Resonance sweeping by a decelerating Galactic bar
• The signatures of the resonances of a large Galactic bar in local velocity space
• New Constraints on the Galactic Bar
• Riding the kinematic waves in the Milky Way disk with Gaia
• The GALAH survey and Gaia DR2: Linking ridges, arches and vertical waves in the kinematics of the Milky Way
• Stellar Kinematic Constraints on Galactic Structure Models Revisited: Bar and Spiral Arm Resonances
• Tree-ring structure of Galactic bar resonance
• A Recent Lindblad Resonance in the Solar Neighbourhood
• On the ridges, undulations & streams in Gaia DR2: Linking the topography of phase-space to the orbital structure of an N-body bar
• Tracing the Hercules stream with Gaia and LAMOST: new evidence for a fast bar in the Milky Way
• Phase Space Structure in the Solar Neighbourhood
• Trapped orbits and solar-neighbourhood kinematics
• Spiral arm crossings inferred from ridges in Gaia stellar velocity distributions
• Escapees from the bar resonances. On the presence of low-eccentricity, metal-rich stars at the Solar vicinity
• Probing the Galaxy's bars via the Hercules stream
• The phase spiral in Gaia DR3
• Radial migration in a stellar galactic disc with thick components
• The origin and fate of the Gaia phase-space snail
• Chemo-kinematics of the Milky Way spiral arms and bar resonances: connection to ridges and moving groups in the Solar vicinity
• Trojans in the Solar Neighborhood
• On the stellar velocity distribution in the solar neighborhood in the light of Gaia DR2
• Trimodal structure of Hercules stream explained by originating from bar resonances
• Dissecting the Phase Space Snail Shell
• The GALAH Survey: Stellar streams and how stellar velocity distributions vary with Galactic longitude, hemisphere and metallicity
• The spiral structure of the Galaxy revealed by CS sources and evidence for the 4:1 resonance
• Stellar chromospheric activity and age relation from open clusters in the LAMOST Survey
• Exploring the origin of moving groups and diagonal ridges by simulations of stellar orbits and birthplaces
• The dynamical origin of the Local arm and the Sun's trapped orbit
• Tracing Hercules in Galactic azimuth with Gaia DR2
• The bar resonances and low angular momentum moving groups in the Galaxy revealed by stellar ages
• Moving groups across Galactocentric radius with Gaia DR3
• From ridges in the velocity distribution to wiggles in the rotation curve
• Combined dynamical effects of the bar and spiral arms in a Galaxy model. Application to the solar neighbourhood
• From ridges to manifolds: 3D characterization of the moving groups in the Milky Way disc
• Metallicity dependence of the Hercules stream in Gaia/RAVE data -- explanation by non-closed orbits
• Age-metallicity dependent stellar kinematics of the Milky Way disc from LAMOST and Gaia
• Correlations between age, kinematics, and chemistry as seen by the RAVE survey
• Asymmetric metallicity patterns in the stellar velocity space with RAVE
• Quantifying Chaos in Models of the Solar Neighbourhood
• Evidence for Co-rotation Origin of Super Metal Rich Stars in LAMOST-Gaia: Multiple Ridges with a Similar Slope in phi versus Lz Plane
• Accelerated phase-mixing in the stellar halo due to a rotating bar
• Gaia DR2 white dwarfs in the Hercules stream

Cited by in corpus (3)

• On the origin of the Hercules group: I. chemical signatures indicating the outer bar origin
• Moving Groups in the Solar Neighborhood with Gaia, APOGEE, GALAH, and LAMOST: Dynamical Effects Gather Gas and the Ensuing Star Formation Plays an Important Role in Shaping the Stellar Velocity Distributions
• CWTHF: Subhalo Identification with Continuous Wavelet Transform