A 6D kinematic census identifies 18 anomalous Cepheids with extreme orbits, including one possibly scattered by globular cluster E3, and finds consistency between dynamical and stellar ages.
The stellar population structure of the Galactic disk
3 Pith papers cite this work. Polarity classification is still indexing.
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Pith papers citing it
abstract
The spatial structure of stellar populations with different chemical abundances in the Milky Way contains a wealth of information on Galactic evolution over cosmic time. We use data on 14,699 red-clump stars from the APOGEE survey, covering 4 kpc <~ R <~ 15 kpc, to determine the structure of mono-abundance populations (MAPs)---stars in narrow bins in [a/Fe] and [Fe/H]---accounting for the complex effects of the APOGEE selection function and the spatially-variable dust obscuration. We determine that all MAPs with enhanced [a/Fe] are centrally concentrated and are well-described as exponentials with a scale length of 2.2+/-0.2 kpc over the whole radial range of the disk. We discover that the surface-density profiles of low-[a/Fe] MAPs are complex: they do not monotonically decrease outwards, but rather display a peak radius ranging from ~5 kpc to ~13 kpc at low [Fe/H]. The extensive radial coverage of the data allows us to measure radial trends in the thickness of each MAP. While high-[a/Fe] MAPs have constant scale heights, low-[a/Fe] MAPs flare. We confirm, now with high-precision abundances, previous results that each MAP contains only a single vertical scale height and that low-[Fe/H], low-[a/Fe] and high-[Fe/H], high-[a/Fe] MAPs have intermediate (h_Z~300 to 600 pc) scale heights that smoothly bridge the traditional thin- and thick-disk divide. That the high-[a/Fe], thick disk components do not flare is strong evidence against their thickness being caused by radial migration. The correspondence between the radial structure and chemical-enrichment age of stellar populations is clear confirmation of the inside-out growth of galactic disks. The details of these relations will constrain the variety of physical conditions under which stars form throughout the MW disk.
representative citing papers
A multiphase ISM grain-size model with low supernova dust yield reproduces observed dust-to-stellar mass ratios and UV luminosity functions at z=7-12 by letting small grains seed rapid metal accretion.
Revised solar photospheric abundances yield Z/X = 0.0187 with C, N, O at 8.46, 7.83, 8.69, preserving the solar modeling discrepancy and revealing a modest volatile-refractory offset from CI chondrites.
citing papers explorer
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Rogue Ones: Orbital census of Galactic Cepheids and their Anomalies
A 6D kinematic census identifies 18 anomalous Cepheids with extreme orbits, including one possibly scattered by globular cluster E3, and finds consistency between dynamical and stellar ages.
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Grain-size evolution and rapid dust growth in high-redshift galaxies
A multiphase ISM grain-size model with low supernova dust yield reproduces observed dust-to-stellar mass ratios and UV luminosity functions at z=7-12 by letting small grains seed rapid metal accretion.
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The chemical make-up of the Sun: A 2020 vision
Revised solar photospheric abundances yield Z/X = 0.0187 with C, N, O at 8.46, 7.83, 8.69, preserving the solar modeling discrepancy and revealing a modest volatile-refractory offset from CI chondrites.