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ABSTRACT We introduce the Sloan Digital Sky Survey (SDSS)/ Apache Point Observatory Galactic Evolution Experiment (APOGEE) value-added catalogue of Galactic globular cluster (GC) stars. The catalogue is the result of a critical search of the APOGEE Data Release 17 (DR17) catalogue for candidate members of all known Galactic GCs. Candidate members are assigned to various GCs on the basis of position in the sky, proper motion, and radial velocity. The catalogue contains a total of 7737 entries for 6422 unique stars associated with 72 Galactic GCs. Full APOGEE DR17 information is provided, including radial velocities and abundances for up to 20 elements. Membership probabilities estimated on the basis of precision radial velocities are made available. Comparisons with chemical compositions derived from the GALactic Archaeology with HERMES (GALAH) survey, as well as optical values from the literature, show good agreement. This catalogue represents a significant increase in the public data base of GC star chemical compositions and kinematics, providing a massive homogeneous data set that will enable a variety of studies. The catalogue in fits format is available for public download from the SDSS-IV DR17 value-added catalogue website.
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This content will become publicly available on September 1, 2026
Bar-spiral interaction induces radial migration and star formation bursts
Context.Central bars and spirals are known to impact significantly the evolution of their host galaxies, both in terms of dynamics and star formation. Their typically different pattern speeds cause them to regularly overlap, which induces fluctuations in bar parameters. Aims.In this paper, we analyze both numerical simulations of disk galaxies and observational data to study the effect of bar-spiral physical overlap on stellar radial migration and star formation in the bar vicinity, as a function of time and galactic azimuth. Methods.We studied three different numerical models, two of which are in a cosmological context, alongside APOGEE DR17 data and the WISE catalog of Galactic HII regions. Results.We find that periodic boosts in stellar radial migration occur when the bar and spiral structures overlap. This mechanism causes net inward migration along the bar leading side, while stars along the bar trailing side and minor axis are shifted outward. The signature of bar-spiral-induced migration is seen between the bar inner Lindbald resonance and well outside its corotation, beyond which other drivers take over. We also find that, in agreement with simulations, APOGEE DR17 stars born at the bar vicinity (which are mostly metal rich) can migrate out to the solar radius while remaining on cold orbits. For the Milky Way, 13% of stars in the solar vicinity with an eccentricity <0.5 were born inside the bar, compared to 5–20% in the simulations. Bar-spiral reconnections also result in periodic starbursts at the bar ends with an enhancement of up to a factor of 4, depending on the strength of the spiral structure. Similarly to the migration bursts, these do not always happen simultaneously at the two sides of the bar, which hints at the importance of odd spiral modes. Data from the WISE catalog suggest this phenomenon is also relevant in our own Galaxy.
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- Award ID(s):
- 2202340
- PAR ID:
- 10655714
- Publisher / Repository:
- Astronomy & Astrophysics
- Date Published:
- Journal Name:
- Astronomy & Astrophysics
- Volume:
- 701
- ISSN:
- 0004-6361
- Page Range / eLocation ID:
- A88
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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