Lian J.Zasowski G.Hasselquist S.Holtzman J.A.Boardman N.Cunha K.José Fernández TrincadoFrinchaboy P.M.Garcia-Hernandez D.A.Nitschelm C.Lane R.R.Thomas D.Zhang K.2025-03-142025-03-142022https://hdl.handle.net/20.500.12740/17179Stellar radial migration plays an important role in reshaping a galaxy's structure and the radial distribution of stellar population properties. In this work, we revisit reported observational evidence for radial migration and quantify its strength using the age-[Fe/H] distribution of stars across the Milky Way with APOGEE data. We find a broken age-[Fe/H] relation in the Galactic disc at r > 6 kpc, with a more pronounced break at larger radii. To quantify the strength of radial migration, we assume stars born at each radius have a unique age and metallicity, and then decompose the metallicity distribution function (MDF) of mono-age young populations into different Gaussian components that originated from various birth radii at rbirth < 13 kpc. We find that, at ages of 2 and 3 Gyr, roughly half the stars were formed within 1 kpc of their present radius, and very few stars (<5 per cent) were formed more than 4 kpc away from their present radius. These results suggest limited short-distance radial migration and inefficient long-distance migration in the Milky Way during the last 3 Gyr. In the very outer disc beyond 15 kpc, the observed age-[Fe/H] distribution is consistent with the prediction of pure radial migration from smaller radii, suggesting a migration origin of the very outer disc. We also estimate intrinsic metallicity gradients at ages of 2 and 3 Gyr of-0.061 and-0.063 dex kpc-1, respectively. © 2022 The Author(s) Published by Oxford University Press on behalf of Royal Astronomical Society.PDFGalaxy: abundancesGalaxy: evolutionGalaxy: formationGalaxy: stellar contentGalaxy: structureArtículohttp://dx.doi.org/10.1093/mnras/stac479