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The origin of apparently young $\alpha$-rich stars in the Galaxy is still amatter of debate in Galactic archaeology, whether they are genuinely young ormight be products of binary evolution and merger/mass accretion. We aim to shedlight on the nature of young $\alpha$-rich stars in the Milky Way by studyingtheir distribution in the Galaxy thanks to an unprecedented sample of giantstars that cover different Galactic regions and have precise asteroseismicages, chemical, and kinematic measurements. We analyze a new sample of $\sim$6000 stars with precise ages coming from asteroseismology. Our sample combinesthe global asteroseismic parameters measured from light curves obtained by theK2 mission with stellar parameters and chemical abundances obtained from APOGEEDR17 and GALAH DR3, then cross-matched with Gaia DR3. We define our sample ofyoung $\alpha$-rich stars and study their chemical, kinematic, and ageproperties. We investigate young $\alpha$-rich stars in different parts of theGalaxy and we find that the fraction of young $\alpha$-rich stars remainsconstant with respect to the number of high-$\alpha$ stars at $\sim$ 10%.Furthermore, young $\alpha$-rich stars have kinematic and chemical propertiessimilar to high-$\alpha$ stars, except for [C/N] ratios. This suggests thatthese stars are not genuinely young, but products of binary evolution andmerger/mass accretion. Under that assumption, we find the fraction of thesestars in the field to be similar to that found recently in clusters. This factsuggests that $\sim$ 10% of the low-$\alpha$ field stars could also have theirages underestimated by asteroseismology. This should be kept in mind when usingasteroseismic ages to interpret results in Galactic archaeology.

K2 results for "young" $\alpha$-rich stars in the Galaxy